diff --git a/cms/djangoapps/contentstore/tests/test_contentstore.py b/cms/djangoapps/contentstore/tests/test_contentstore.py
index 232b68ecc8..1e6ab8cd86 100644
--- a/cms/djangoapps/contentstore/tests/test_contentstore.py
+++ b/cms/djangoapps/contentstore/tests/test_contentstore.py
@@ -271,7 +271,7 @@ class ContentStoreToyCourseTest(ModuleStoreTestCase):
         )
         self.assertTrue(getattr(draft_problem, 'is_draft', False))
 
-        #now requery with depth
+        # now requery with depth
         course = modulestore('draft').get_item(
             Location(['i4x', 'edX', 'simple', 'course', '2012_Fall', None]),
             depth=None
@@ -539,7 +539,7 @@ class ContentStoreToyCourseTest(ModuleStoreTestCase):
             on_disk = loads(grading_policy.read())
             self.assertEqual(on_disk, course.grading_policy)
 
-        #check for policy.json
+        # check for policy.json
         self.assertTrue(filesystem.exists('policy.json'))
 
         # compare what's on disk to what we have in the course module
@@ -990,7 +990,7 @@ class ContentStoreTest(ModuleStoreTestCase):
 
     def test_metadata_inheritance(self):
         module_store = modulestore('direct')
-        import_from_xml(module_store, 'common/test/data/', ['full'])
+        import_from_xml(module_store, 'common/test/data/', ['full'], verbose=True)
 
         course = module_store.get_item(Location(['i4x', 'edX', 'full', 'course', '6.002_Spring_2012', None]))
 
diff --git a/cms/djangoapps/contentstore/tests/test_course_settings.py b/cms/djangoapps/contentstore/tests/test_course_settings.py
index 2a4ff46038..c1b7a9fa0e 100644
--- a/cms/djangoapps/contentstore/tests/test_course_settings.py
+++ b/cms/djangoapps/contentstore/tests/test_course_settings.py
@@ -151,22 +151,16 @@ class CourseDetailsViewTest(CourseTestCase):
         self.assertEqual(details['intro_video'], encoded.get('intro_video', None), context + " intro_video not ==")
         self.assertEqual(details['effort'], encoded['effort'], context + " efforts not ==")
 
-    @staticmethod
-    def struct_to_datetime(struct_time):
-        return datetime.datetime(*struct_time[:6], tzinfo=UTC())
-
     def compare_date_fields(self, details, encoded, context, field):
         if details[field] is not None:
             date = Date()
             if field in encoded and encoded[field] is not None:
-                encoded_encoded = date.from_json(encoded[field])
-                dt1 = CourseDetailsViewTest.struct_to_datetime(encoded_encoded)
+                dt1 = date.from_json(encoded[field])
 
                 if isinstance(details[field], datetime.datetime):
                     dt2 = details[field]
                 else:
-                    details_encoded = date.from_json(details[field])
-                    dt2 = CourseDetailsViewTest.struct_to_datetime(details_encoded)
+                    dt2 = date.from_json(details[field])
 
                 expected_delta = datetime.timedelta(0)
                 self.assertEqual(dt1 - dt2, expected_delta, str(dt1) + "!=" + str(dt2) + " at " + context)
diff --git a/cms/djangoapps/contentstore/views/assets.py b/cms/djangoapps/contentstore/views/assets.py
index b5041d3e9f..2be2cfafb8 100644
--- a/cms/djangoapps/contentstore/views/assets.py
+++ b/cms/djangoapps/contentstore/views/assets.py
@@ -62,7 +62,7 @@ def asset_index(request, org, course, name):
         asset_id = asset['_id']
         display_info = {}
         display_info['displayname'] = asset['displayname']
-        display_info['uploadDate'] = get_default_time_display(asset['uploadDate'].timetuple())
+        display_info['uploadDate'] = get_default_time_display(asset['uploadDate'])
 
         asset_location = StaticContent.compute_location(asset_id['org'], asset_id['course'], asset_id['name'])
         display_info['url'] = StaticContent.get_url_path_from_location(asset_location)
@@ -131,7 +131,7 @@ def upload_asset(request, org, course, coursename):
     readback = contentstore().find(content.location)
 
     response_payload = {'displayname': content.name,
-                        'uploadDate': get_default_time_display(readback.last_modified_at.timetuple()),
+                        'uploadDate': get_default_time_display(readback.last_modified_at),
                         'url': StaticContent.get_url_path_from_location(content.location),
                         'thumb_url': StaticContent.get_url_path_from_location(thumbnail_location) if thumbnail_content is not None else None,
                         'msg': 'Upload completed'
@@ -231,7 +231,7 @@ def generate_export_course(request, org, course, name):
     logging.debug('root = {0}'.format(root_dir))
 
     export_to_xml(modulestore('direct'), contentstore(), loc, root_dir, name, modulestore())
-    #filename = root_dir / name + '.tar.gz'
+    # filename = root_dir / name + '.tar.gz'
 
     logging.debug('tar file being generated at {0}'.format(export_file.name))
     tar_file = tarfile.open(name=export_file.name, mode='w:gz')
diff --git a/cms/djangoapps/contentstore/views/course.py b/cms/djangoapps/contentstore/views/course.py
index 07f6b9669c..e1c176eebe 100644
--- a/cms/djangoapps/contentstore/views/course.py
+++ b/cms/djangoapps/contentstore/views/course.py
@@ -2,7 +2,6 @@
 Views related to operations on course objects
 """
 import json
-import time
 
 from django.contrib.auth.decorators import login_required
 from django_future.csrf import ensure_csrf_cookie
@@ -32,6 +31,8 @@ from .component import OPEN_ENDED_COMPONENT_TYPES, \
      NOTE_COMPONENT_TYPES, ADVANCED_COMPONENT_POLICY_KEY
 
 from django_comment_common.utils import seed_permissions_roles
+import datetime
+from django.utils.timezone import UTC
 
 # TODO: should explicitly enumerate exports with __all__
 
@@ -130,7 +131,7 @@ def create_new_course(request):
         new_course.display_name = display_name
 
     # set a default start date to now
-    new_course.start = time.gmtime()
+    new_course.start = datetime.datetime.now(UTC())
 
     initialize_course_tabs(new_course)
 
@@ -357,49 +358,49 @@ def course_advanced_updates(request, org, course, name):
         # Whether or not to filter the tabs key out of the settings metadata
         filter_tabs = True
 
-        #Check to see if the user instantiated any advanced components. This is a hack
-        #that does the following : 
-        #   1) adds/removes the open ended panel tab to a course automatically if the user 
+        # Check to see if the user instantiated any advanced components. This is a hack
+        # that does the following :
+        #   1) adds/removes the open ended panel tab to a course automatically if the user
         #   has indicated that they want to edit the combinedopendended or peergrading module
         #   2) adds/removes the notes panel tab to a course automatically if the user has
         #   indicated that they want the notes module enabled in their course
         # TODO refactor the above into distinct advanced policy settings
         if ADVANCED_COMPONENT_POLICY_KEY in request_body:
-            #Get the course so that we can scrape current tabs
+            # Get the course so that we can scrape current tabs
             course_module = modulestore().get_item(location)
 
-            #Maps tab types to components 
+            # Maps tab types to components
             tab_component_map = {
-                'open_ended': OPEN_ENDED_COMPONENT_TYPES, 
+                'open_ended': OPEN_ENDED_COMPONENT_TYPES,
                 'notes': NOTE_COMPONENT_TYPES,
             }
 
-            #Check to see if the user instantiated any notes or open ended components
+            # Check to see if the user instantiated any notes or open ended components
             for tab_type in tab_component_map.keys():
                 component_types = tab_component_map.get(tab_type)
                 found_ac_type = False
                 for ac_type in component_types:
                     if ac_type in request_body[ADVANCED_COMPONENT_POLICY_KEY]:
-                        #Add tab to the course if needed
+                        # Add tab to the course if needed
                         changed, new_tabs = add_extra_panel_tab(tab_type, course_module)
-                        #If a tab has been added to the course, then send the metadata along to CourseMetadata.update_from_json
+                        # If a tab has been added to the course, then send the metadata along to CourseMetadata.update_from_json
                         if changed:
                             course_module.tabs = new_tabs
                             request_body.update({'tabs': new_tabs})
-                            #Indicate that tabs should not be filtered out of the metadata
+                            # Indicate that tabs should not be filtered out of the metadata
                             filter_tabs = False
-                        #Set this flag to avoid the tab removal code below.
+                        # Set this flag to avoid the tab removal code below.
                         found_ac_type = True
                         break
-                #If we did not find a module type in the advanced settings,
+                # If we did not find a module type in the advanced settings,
                 # we may need to remove the tab from the course.
                 if not found_ac_type:
-                    #Remove tab from the course if needed
+                    # Remove tab from the course if needed
                     changed, new_tabs = remove_extra_panel_tab(tab_type, course_module)
                     if changed:
                         course_module.tabs = new_tabs
                         request_body.update({'tabs': new_tabs})
-                        #Indicate that tabs should *not* be filtered out of the metadata
+                        # Indicate that tabs should *not* be filtered out of the metadata
                         filter_tabs = False
 
         response_json = json.dumps(CourseMetadata.update_from_json(location,
diff --git a/cms/djangoapps/models/settings/course_details.py b/cms/djangoapps/models/settings/course_details.py
index 0dbb47b31b..28dba473f2 100644
--- a/cms/djangoapps/models/settings/course_details.py
+++ b/cms/djangoapps/models/settings/course_details.py
@@ -3,26 +3,26 @@ from xmodule.modulestore.exceptions import ItemNotFoundError
 from xmodule.modulestore.inheritance import own_metadata
 import json
 from json.encoder import JSONEncoder
-import time
 from contentstore.utils import get_modulestore
 from models.settings import course_grading
 from contentstore.utils import update_item
 from xmodule.fields import Date
 import re
 import logging
+import datetime
 
 
 class CourseDetails(object):
     def __init__(self, location):
-        self.course_location = location    # a Location obj
+        self.course_location = location  # a Location obj
         self.start_date = None  # 'start'
-        self.end_date = None    # 'end'
+        self.end_date = None  # 'end'
         self.enrollment_start = None
         self.enrollment_end = None
-        self.syllabus = None    # a pdf file asset
-        self.overview = ""      # html to render as the overview
-        self.intro_video = None    # a video pointer
-        self.effort = None      # int hours/week
+        self.syllabus = None  # a pdf file asset
+        self.overview = ""  # html to render as the overview
+        self.intro_video = None  # a video pointer
+        self.effort = None  # int hours/week
 
     @classmethod
     def fetch(cls, course_location):
@@ -73,9 +73,9 @@ class CourseDetails(object):
         """
         Decode the json into CourseDetails and save any changed attrs to the db
         """
-        ## TODO make it an error for this to be undefined & for it to not be retrievable from modulestore
+        # # TODO make it an error for this to be undefined & for it to not be retrievable from modulestore
         course_location = jsondict['course_location']
-        ## Will probably want to cache the inflight courses because every blur generates an update
+        # # Will probably want to cache the inflight courses because every blur generates an update
         descriptor = get_modulestore(course_location).get_item(course_location)
 
         dirty = False
@@ -181,7 +181,7 @@ class CourseSettingsEncoder(json.JSONEncoder):
             return obj.__dict__
         elif isinstance(obj, Location):
             return obj.dict()
-        elif isinstance(obj, time.struct_time):
+        elif isinstance(obj, datetime.datetime):
             return Date().to_json(obj)
         else:
             return JSONEncoder.default(self, obj)
diff --git a/cms/templates/edit_subsection.html b/cms/templates/edit_subsection.html
index 9bb9b3a506..4aae070ca1 100644
--- a/cms/templates/edit_subsection.html
+++ b/cms/templates/edit_subsection.html
@@ -1,7 +1,7 @@
 <%inherit file="base.html" />
 <%!
    import logging
-   from xmodule.util.date_utils import get_time_struct_display
+   from xmodule.util.date_utils import get_default_time_display
 %>
 
 <%! from django.core.urlresolvers import reverse %>
@@ -36,11 +36,15 @@
         <div class="datepair" data-language="javascript">
           <div class="field field-start-date">
             <label for="start_date">Release Day</label>
-            <input type="text" id="start_date" name="start_date" value="${get_time_struct_display(subsection.lms.start, '%m/%d/%Y')}" placeholder="MM/DD/YYYY" class="date" size='15' autocomplete="off"/>
+            <input type="text" id="start_date" name="start_date" 
+                value="${subsection.lms.start.strftime('%m/%d/%Y')}" 
+                placeholder="MM/DD/YYYY" class="date" size='15' autocomplete="off"/>
           </div>
           <div class="field field-start-time">
             <label for="start_time">Release Time (<abbr title="Coordinated Universal Time">UTC</abbr>)</label>
-            <input type="text" id="start_time" name="start_time" value="${get_time_struct_display(subsection.lms.start, '%H:%M')}" placeholder="HH:MM" class="time" size='10' autocomplete="off"/>
+            <input type="text" id="start_time" name="start_time" 
+                value="${subsection.lms.start.strftime('%H:%M')}" 
+                placeholder="HH:MM" class="time" size='10' autocomplete="off"/>
           </div>
         </div>
         % if subsection.lms.start != parent_item.lms.start and subsection.lms.start:
@@ -48,7 +52,7 @@
             <p class="notice">The date above differs from the release date of ${parent_item.display_name_with_default}, which is unset.
             % else:
             <p class="notice">The date above differs from the release date of ${parent_item.display_name_with_default} –
-                ${get_time_struct_display(parent_item.lms.start, '%m/%d/%Y at %H:%M UTC')}.
+                ${get_default_time_display(parent_item.lms.start)}.
             % endif
             <a href="#" class="sync-date no-spinner">Sync to ${parent_item.display_name_with_default}.</a></p>
         % endif
@@ -65,11 +69,15 @@
       <div class="datepair date-setter">
         <div class="field field-start-date">
           <label for="due_date">Due Day</label>
-          <input type="text" id="due_date" name="due_date" value="${get_time_struct_display(subsection.lms.due, '%m/%d/%Y')}" placeholder="MM/DD/YYYY" class="date" size='15' autocomplete="off"/>
+          <input type="text" id="due_date" name="due_date" 
+          value="${subsection.lms.due.strftime('%m/%d/%Y') if subsection.lms.due else ''}" 
+          placeholder="MM/DD/YYYY" class="date" size='15' autocomplete="off"/>
         </div>
         <div class="field field-start-time">
           <label for="due_time">Due Time (<abbr title="Coordinated Universal Time">UTC</abbr>)</label>
-          <input type="text" id="due_time" name="due_time" value="${get_time_struct_display(subsection.lms.due, '%H:%M')}" placeholder="HH:MM" class="time" size='10' autocomplete="off"/>
+          <input type="text" id="due_time" name="due_time" 
+            value="${subsection.lms.due.strftime('%H:%M') if subsection.lms.due else ''}" 
+            placeholder="HH:MM" class="time" size='10' autocomplete="off"/>
         </div>
         <a href="#" class="remove-date">Remove due date</a>
       </div>
diff --git a/cms/templates/overview.html b/cms/templates/overview.html
index d327c8b324..0b82d76943 100644
--- a/cms/templates/overview.html
+++ b/cms/templates/overview.html
@@ -1,7 +1,7 @@
 <%inherit file="base.html" />
 <%!
    import logging
-   from xmodule.util.date_utils import get_time_struct_display
+   from xmodule.util import date_utils
 %>
 <%! from django.core.urlresolvers import reverse %>
 <%block name="title">Course Outline</%block>
@@ -154,14 +154,15 @@
               <h3 class="section-name" data-name="${section.display_name_with_default | h}"></h3>
               <div class="section-published-date">
                 <%
-                  start_date_str = get_time_struct_display(section.lms.start, '%m/%d/%Y')
-                  start_time_str = get_time_struct_display(section.lms.start, '%H:%M')
+                  start_date_str = section.lms.start.strftime('%m/%d/%Y')
+                  start_time_str = section.lms.start.strftime('%H:%M')
                 %>
                 %if section.lms.start is None:
                   <span class="published-status">This section has not been released.</span>
                   <a href="#" class="schedule-button" data-date="" data-time="" data-id="${section.location}">Schedule</a>
                 %else:
-                  <span class="published-status"><strong>Will Release:</strong> ${get_time_struct_display(section.lms.start, '%m/%d/%Y at %H:%M UTC')}</span>
+                  <span class="published-status"><strong>Will Release:</strong> 
+                  ${date_utils.get_default_time_display(section.lms.start)}</span>
                   <a href="#" class="edit-button" data-date="${start_date_str}" data-time="${start_time_str}" data-id="${section.location}">Edit</a>
                 %endif
               </div>
diff --git a/common/djangoapps/contentserver/middleware.py b/common/djangoapps/contentserver/middleware.py
index 8e9e70046d..7deb0901aa 100644
--- a/common/djangoapps/contentserver/middleware.py
+++ b/common/djangoapps/contentserver/middleware.py
@@ -1,7 +1,4 @@
-import logging
-import time
-
-from django.http import HttpResponse, Http404, HttpResponseNotModified
+from django.http import HttpResponse, HttpResponseNotModified
 
 from xmodule.contentstore.django import contentstore
 from xmodule.contentstore.content import StaticContent, XASSET_LOCATION_TAG
@@ -20,7 +17,7 @@ class StaticContentServer(object):
                 # return a 'Bad Request' to browser as we have a malformed Location
                 response = HttpResponse()
                 response.status_code = 400
-                return response     
+                return response
 
             # first look in our cache so we don't have to round-trip to the DB
             content = get_cached_content(loc)
diff --git a/common/djangoapps/student/management/commands/pearson_make_tc_registration.py b/common/djangoapps/student/management/commands/pearson_make_tc_registration.py
index b10cf143a0..50e56bb4be 100644
--- a/common/djangoapps/student/management/commands/pearson_make_tc_registration.py
+++ b/common/djangoapps/student/management/commands/pearson_make_tc_registration.py
@@ -1,5 +1,4 @@
 from optparse import make_option
-from time import strftime
 
 from django.contrib.auth.models import User
 from django.core.management.base import BaseCommand, CommandError
@@ -128,8 +127,8 @@ class Command(BaseCommand):
             exam = CourseDescriptor.TestCenterExam(course_id, exam_name, exam_info)
             # update option values for date_first and date_last to use YYYY-MM-DD format
             # instead of YYYY-MM-DDTHH:MM
-            our_options['eligibility_appointment_date_first'] = strftime("%Y-%m-%d", exam.first_eligible_appointment_date)
-            our_options['eligibility_appointment_date_last'] = strftime("%Y-%m-%d", exam.last_eligible_appointment_date)
+            our_options['eligibility_appointment_date_first'] = exam.first_eligible_appointment_date.strftime("%Y-%m-%d")
+            our_options['eligibility_appointment_date_last'] = exam.last_eligible_appointment_date.strftime("%Y-%m-%d")
 
         if exam is None:
             raise CommandError("Exam for course_id {} does not exist".format(course_id))
diff --git a/common/djangoapps/student/models.py b/common/djangoapps/student/models.py
index ab68b05f4b..57f3d756b9 100644
--- a/common/djangoapps/student/models.py
+++ b/common/djangoapps/student/models.py
@@ -16,7 +16,6 @@ import json
 import logging
 import uuid
 from random import randint
-from time import strftime
 
 
 from django.conf import settings
@@ -54,7 +53,7 @@ class UserProfile(models.Model):
     class Meta:
         db_table = "auth_userprofile"
 
-    ## CRITICAL TODO/SECURITY
+    # # CRITICAL TODO/SECURITY
     # Sanitize all fields.
     # This is not visible to other users, but could introduce holes later
     user = models.OneToOneField(User, unique=True, db_index=True, related_name='profile')
@@ -429,8 +428,8 @@ class TestCenterRegistration(models.Model):
         registration.course_id = exam.course_id
         registration.accommodation_request = accommodation_request.strip()
         registration.exam_series_code = exam.exam_series_code
-        registration.eligibility_appointment_date_first = strftime("%Y-%m-%d", exam.first_eligible_appointment_date)
-        registration.eligibility_appointment_date_last = strftime("%Y-%m-%d", exam.last_eligible_appointment_date)
+        registration.eligibility_appointment_date_first = exam.first_eligible_appointment_date.strftime("%Y-%m-%d")
+        registration.eligibility_appointment_date_last = exam.last_eligible_appointment_date.strftime("%Y-%m-%d")
         registration.client_authorization_id = cls._create_client_authorization_id()
         # accommodation_code remains blank for now, along with Pearson confirmation information
         return registration
@@ -598,7 +597,7 @@ def unique_id_for_user(user):
     return h.hexdigest()
 
 
-## TODO: Should be renamed to generic UserGroup, and possibly
+# # TODO: Should be renamed to generic UserGroup, and possibly
 # Given an optional field for type of group
 class UserTestGroup(models.Model):
     users = models.ManyToManyField(User, db_index=True)
@@ -626,7 +625,7 @@ class Registration(models.Model):
     def activate(self):
         self.user.is_active = True
         self.user.save()
-        #self.delete()
+        # self.delete()
 
 
 class PendingNameChange(models.Model):
@@ -648,7 +647,7 @@ class CourseEnrollment(models.Model):
     created = models.DateTimeField(auto_now_add=True, null=True, db_index=True)
 
     class Meta:
-        unique_together = (('user', 'course_id'), )
+        unique_together = (('user', 'course_id'),)
 
     def __unicode__(self):
         return "[CourseEnrollment] %s: %s (%s)" % (self.user, self.course_id, self.created)
@@ -667,12 +666,12 @@ class CourseEnrollmentAllowed(models.Model):
     created = models.DateTimeField(auto_now_add=True, null=True, db_index=True)
 
     class Meta:
-        unique_together = (('email', 'course_id'), )
+        unique_together = (('email', 'course_id'),)
 
     def __unicode__(self):
         return "[CourseEnrollmentAllowed] %s: %s (%s)" % (self.email, self.course_id, self.created)
 
-#cache_relation(User.profile)
+# cache_relation(User.profile)
 
 #### Helper methods for use from python manage.py shell and other classes.
 
diff --git a/common/djangoapps/xmodule_modifiers.py b/common/djangoapps/xmodule_modifiers.py
index 45691cd854..570b38c942 100644
--- a/common/djangoapps/xmodule_modifiers.py
+++ b/common/djangoapps/xmodule_modifiers.py
@@ -1,7 +1,6 @@
 import re
 import json
 import logging
-import time
 import static_replace
 
 from django.conf import settings
@@ -9,6 +8,8 @@ from functools import wraps
 from mitxmako.shortcuts import render_to_string
 from xmodule.seq_module import SequenceModule
 from xmodule.vertical_module import VerticalModule
+import datetime
+from django.utils.timezone import UTC
 
 log = logging.getLogger("mitx.xmodule_modifiers")
 
@@ -83,7 +84,7 @@ def grade_histogram(module_id):
     cursor.execute(q, [module_id])
 
     grades = list(cursor.fetchall())
-    grades.sort(key=lambda x: x[0])          # Add ORDER BY to sql query?
+    grades.sort(key=lambda x: x[0])  # Add ORDER BY to sql query?
     if len(grades) >= 1 and grades[0][0] is None:
         return []
     return grades
@@ -101,7 +102,7 @@ def add_histogram(get_html, module, user):
     @wraps(get_html)
     def _get_html():
 
-        if type(module) in [SequenceModule, VerticalModule]:  	# TODO: make this more general, eg use an XModule attribute instead
+        if type(module) in [SequenceModule, VerticalModule]:  # TODO: make this more general, eg use an XModule attribute instead
             return get_html()
 
         module_id = module.id
@@ -132,7 +133,7 @@ def add_histogram(get_html, module, user):
 
         # useful to indicate to staff if problem has been released or not
         # TODO (ichuang): use _has_access_descriptor.can_load in lms.courseware.access, instead of now>mstart comparison here
-        now = time.gmtime()
+        now = datetime.datetime.now(UTC())
         is_released = "unknown"
         mstart = module.descriptor.lms.start
 
diff --git a/common/lib/capa/capa/inputtypes.py b/common/lib/capa/capa/inputtypes.py
index 65280d6d29..3680379406 100644
--- a/common/lib/capa/capa/inputtypes.py
+++ b/common/lib/capa/capa/inputtypes.py
@@ -144,11 +144,11 @@ class InputTypeBase(object):
         self.tag = xml.tag
         self.system = system
 
-        ## NOTE: ID should only come from one place.  If it comes from multiple,
-        ## we use state first, XML second (in case the xml changed, but we have
-        ## existing state with an old id). Since we don't make this guarantee,
-        ## we can swap this around in the future if there's a more logical
-        ## order.
+        # # NOTE: ID should only come from one place.  If it comes from multiple,
+        # # we use state first, XML second (in case the xml changed, but we have
+        # # existing state with an old id). Since we don't make this guarantee,
+        # # we can swap this around in the future if there's a more logical
+        # # order.
 
         self.input_id = state.get('id', xml.get('id'))
         if self.input_id is None:
@@ -769,7 +769,7 @@ class MatlabInput(CodeInput):
 
         # construct xqueue headers
         qinterface = self.system.xqueue['interface']
-        qtime = datetime.strftime(datetime.utcnow(), xqueue_interface.dateformat)
+        qtime = datetime.utcnow().strftime(xqueue_interface.dateformat)
         callback_url = self.system.xqueue['construct_callback']('ungraded_response')
         anonymous_student_id = self.system.anonymous_student_id
         queuekey = xqueue_interface.make_hashkey(str(self.system.seed) + qtime +
diff --git a/common/lib/xmodule/xmodule/capa_module.py b/common/lib/xmodule/xmodule/capa_module.py
index 9e0ab16203..51b20c12ea 100644
--- a/common/lib/xmodule/xmodule/capa_module.py
+++ b/common/lib/xmodule/xmodule/capa_module.py
@@ -11,7 +11,7 @@ import sys
 from pkg_resources import resource_string
 
 from capa.capa_problem import LoncapaProblem
-from capa.responsetypes import StudentInputError,\
+from capa.responsetypes import StudentInputError, \
     ResponseError, LoncapaProblemError
 from capa.util import convert_files_to_filenames
 from .progress import Progress
@@ -20,7 +20,7 @@ from xmodule.raw_module import RawDescriptor
 from xmodule.exceptions import NotFoundError, ProcessingError
 from xblock.core import Scope, String, Boolean, Object
 from .fields import Timedelta, Date, StringyInteger, StringyFloat
-from xmodule.util.date_utils import time_to_datetime
+from django.utils.timezone import UTC
 
 log = logging.getLogger("mitx.courseware")
 
@@ -134,7 +134,7 @@ class CapaModule(CapaFields, XModule):
     def __init__(self, system, location, descriptor, model_data):
         XModule.__init__(self, system, location, descriptor, model_data)
 
-        due_date = time_to_datetime(self.due)
+        due_date = self.due
 
         if self.graceperiod is not None and due_date:
             self.close_date = due_date + self.graceperiod
@@ -502,7 +502,7 @@ class CapaModule(CapaFields, XModule):
         Is it now past this problem's due date, including grace period?
         """
         return (self.close_date is not None and
-                datetime.datetime.utcnow() > self.close_date)
+                datetime.datetime.now(UTC()) > self.close_date)
 
     def closed(self):
         ''' Is the student still allowed to submit answers? '''
diff --git a/common/lib/xmodule/xmodule/course_module.py b/common/lib/xmodule/xmodule/course_module.py
index 063e53aef4..66d53b43ec 100644
--- a/common/lib/xmodule/xmodule/course_module.py
+++ b/common/lib/xmodule/xmodule/course_module.py
@@ -4,7 +4,6 @@ from math import exp
 from lxml import etree
 from path import path  # NOTE (THK): Only used for detecting presence of syllabus
 import requests
-import time
 from datetime import datetime
 
 import dateutil.parser
@@ -14,11 +13,11 @@ from xmodule.seq_module import SequenceDescriptor, SequenceModule
 from xmodule.timeparse import parse_time
 from xmodule.util.decorators import lazyproperty
 from xmodule.graders import grader_from_conf
-from xmodule.util.date_utils import time_to_datetime
 import json
 
 from xblock.core import Scope, List, String, Object, Boolean
 from .fields import Date
+from django.utils.timezone import UTC
 
 
 log = logging.getLogger(__name__)
@@ -219,8 +218,7 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
         msg = None
         if self.start is None:
             msg = "Course loaded without a valid start date. id = %s" % self.id
-            # hack it -- start in 1970
-            self.start = time.gmtime(0)
+            self.start = datetime.now(UTC())
             log.critical(msg)
             self.system.error_tracker(msg)
 
@@ -392,7 +390,7 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
                 textbook_xml_object.set('book_url', textbook.book_url)
 
             xml_object.append(textbook_xml_object)
-        
+
         return xml_object
 
     def has_ended(self):
@@ -403,10 +401,10 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
         if self.end is None:
             return False
 
-        return time.gmtime() > self.end
+        return datetime.now(UTC()) > self.end
 
     def has_started(self):
-        return time.gmtime() > self.start
+        return datetime.now(UTC()) > self.start
 
     @property
     def grader(self):
@@ -547,14 +545,16 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
 
         announcement = self.announcement
         if announcement is not None:
-            announcement = time_to_datetime(announcement)
+            announcement = announcement
 
         try:
             start = dateutil.parser.parse(self.advertised_start)
+            if start.tzinfo is None:
+                start = start.replace(tzinfo=UTC())
         except (ValueError, AttributeError):
-            start = time_to_datetime(self.start)
+            start = self.start
 
-        now = datetime.utcnow()
+        now = datetime.now(UTC())
 
         return announcement, start, now
 
@@ -656,7 +656,7 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
         elif self.advertised_start is None and self.start is None:
             return 'TBD'
         else:
-            return time.strftime("%b %d, %Y", self.advertised_start or self.start)
+            return (self.advertised_start or self.start).strftime("%b %d, %Y")
 
     @property
     def end_date_text(self):
@@ -665,7 +665,7 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
 
         If the course does not have an end date set (course.end is None), an empty string will be returned.
         """
-        return '' if self.end is None else time.strftime("%b %d, %Y", self.end)
+        return '' if self.end is None else self.end.strftime("%b %d, %Y")
 
     @property
     def forum_posts_allowed(self):
@@ -673,7 +673,7 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
             blackout_periods = [(parse_time(start), parse_time(end))
                                 for start, end
                                 in self.discussion_blackouts]
-            now = time.gmtime()
+            now = datetime.now(UTC())
             for start, end in blackout_periods:
                 if start <= now <= end:
                     return False
@@ -699,7 +699,8 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
             self.last_eligible_appointment_date = self._try_parse_time('Last_Eligible_Appointment_Date')  # or self.first_eligible_appointment_date
             if self.last_eligible_appointment_date is None:
                 raise ValueError("Last appointment date must be specified")
-            self.registration_start_date = self._try_parse_time('Registration_Start_Date') or time.gmtime(0)
+            self.registration_start_date = (self._try_parse_time('Registration_Start_Date') or
+                datetime.utcfromtimestamp(0))
             self.registration_end_date = self._try_parse_time('Registration_End_Date') or self.last_eligible_appointment_date
             # do validation within the exam info:
             if self.registration_start_date > self.registration_end_date:
@@ -725,32 +726,32 @@ class CourseDescriptor(CourseFields, SequenceDescriptor):
                 return None
 
         def has_started(self):
-            return time.gmtime() > self.first_eligible_appointment_date
+            return datetime.now(UTC()) > self.first_eligible_appointment_date
 
         def has_ended(self):
-            return time.gmtime() > self.last_eligible_appointment_date
+            return datetime.now(UTC()) > self.last_eligible_appointment_date
 
         def has_started_registration(self):
-            return time.gmtime() > self.registration_start_date
+            return datetime.now(UTC()) > self.registration_start_date
 
         def has_ended_registration(self):
-            return time.gmtime() > self.registration_end_date
+            return datetime.now(UTC()) > self.registration_end_date
 
         def is_registering(self):
-            now = time.gmtime()
+            now = datetime.now(UTC())
             return now >= self.registration_start_date and now <= self.registration_end_date
 
         @property
         def first_eligible_appointment_date_text(self):
-            return time.strftime("%b %d, %Y", self.first_eligible_appointment_date)
+            return datetime.strftime("%b %d, %Y", self.first_eligible_appointment_date)
 
         @property
         def last_eligible_appointment_date_text(self):
-            return time.strftime("%b %d, %Y", self.last_eligible_appointment_date)
+            return datetime.strftime("%b %d, %Y", self.last_eligible_appointment_date)
 
         @property
         def registration_end_date_text(self):
-            return time.strftime("%b %d, %Y at %H:%M UTC", self.registration_end_date)
+            return datetime.strftime("%b %d, %Y at %H:%M UTC", self.registration_end_date)
 
     @property
     def current_test_center_exam(self):
diff --git a/common/lib/xmodule/xmodule/fields.py b/common/lib/xmodule/xmodule/fields.py
index 3d56b7941e..3164c062bb 100644
--- a/common/lib/xmodule/xmodule/fields.py
+++ b/common/lib/xmodule/xmodule/fields.py
@@ -2,19 +2,19 @@ import time
 import logging
 import re
 
-from datetime import timedelta
 from xblock.core import ModelType
 import datetime
 import dateutil.parser
 
 from xblock.core import Integer, Float, Boolean
+from django.utils.timezone import UTC
 
 log = logging.getLogger(__name__)
 
 
 class Date(ModelType):
     '''
-    Date fields know how to parse and produce json (iso) compatible formats.
+    Date fields know how to parse and produce json (iso) compatible formats. Converts to tz aware datetimes.
     '''
     def from_json(self, field):
         """
@@ -27,11 +27,15 @@ class Date(ModelType):
         elif field is "":
             return None
         elif isinstance(field, basestring):
-            d = dateutil.parser.parse(field)
-            return d.utctimetuple()
+            result = dateutil.parser.parse(field)
+            if result.tzinfo is None:
+                result = result.replace(tzinfo=UTC())
+            return result
         elif isinstance(field, (int, long, float)):
-            return time.gmtime(field / 1000)
+            return datetime.datetime.fromtimestamp(field / 1000, UTC())
         elif isinstance(field, time.struct_time):
+            return datetime.datetime.fromtimestamp(time.mktime(field), UTC())
+        elif isinstance(field, datetime.datetime):
             return field
         else:
             msg = "Field {0} has bad value '{1}'".format(
@@ -49,7 +53,11 @@ class Date(ModelType):
             # struct_times are always utc
             return time.strftime('%Y-%m-%dT%H:%M:%SZ', value)
         elif isinstance(value, datetime.datetime):
-            return value.isoformat() + 'Z'
+            if value.tzinfo is None or value.utcoffset().total_seconds() == 0:
+                # isoformat adds +00:00 rather than Z
+                return value.strftime('%Y-%m-%dT%H:%M:%SZ')
+            else:
+                return value.isoformat()
 
 
 TIMEDELTA_REGEX = re.compile(r'^((?P<days>\d+?) day(?:s?))?(\s)?((?P<hours>\d+?) hour(?:s?))?(\s)?((?P<minutes>\d+?) minute(?:s)?)?(\s)?((?P<seconds>\d+?) second(?:s)?)?$')
@@ -74,7 +82,7 @@ class Timedelta(ModelType):
         for (name, param) in parts.iteritems():
             if param:
                 time_params[name] = int(param)
-        return timedelta(**time_params)
+        return datetime.timedelta(**time_params)
 
     def to_json(self, value):
         values = []
@@ -93,7 +101,7 @@ class StringyInteger(Integer):
     def from_json(self, value):
         try:
             return int(value)
-        except:
+        except Exception:
             return None
 
 
diff --git a/common/lib/xmodule/xmodule/foldit_module.py b/common/lib/xmodule/xmodule/foldit_module.py
index 62c5ea416e..5ab1b327c6 100644
--- a/common/lib/xmodule/xmodule/foldit_module.py
+++ b/common/lib/xmodule/xmodule/foldit_module.py
@@ -8,7 +8,6 @@ from xmodule.x_module import XModule
 from xmodule.xml_module import XmlDescriptor
 from xblock.core import Scope, Integer, String
 from .fields import Date
-from xmodule.util.date_utils import time_to_datetime
 
 
 log = logging.getLogger(__name__)
@@ -31,9 +30,7 @@ class FolditModule(FolditFields, XModule):
     css = {'scss': [resource_string(__name__, 'css/foldit/leaderboard.scss')]}
 
     def __init__(self, *args, **kwargs):
-        XModule.__init__(self, *args, **kwargs)
         """
-
         Example:
          <foldit show_basic_score="true"
             required_level="4"
@@ -42,8 +39,8 @@ class FolditModule(FolditFields, XModule):
             required_sublevel_half_credit="3"
             show_leaderboard="false"/>
         """
-
-        self.due_time = time_to_datetime(self.due)
+        XModule.__init__(self, *args, **kwargs)
+        self.due_time = self.due
 
     def is_complete(self):
         """
@@ -102,7 +99,7 @@ class FolditModule(FolditFields, XModule):
         from foldit.models import Score
 
         leaders = [(e['username'], e['score']) for e in Score.get_tops_n(10)]
-        leaders.sort(key=lambda x: -x[1])
+        leaders.sort(key=lambda x:-x[1])
 
         return leaders
 
diff --git a/common/lib/xmodule/xmodule/modulestore/draft.py b/common/lib/xmodule/xmodule/modulestore/draft.py
index c16c7403a9..048aea8867 100644
--- a/common/lib/xmodule/xmodule/modulestore/draft.py
+++ b/common/lib/xmodule/xmodule/modulestore/draft.py
@@ -4,6 +4,7 @@ from . import ModuleStoreBase, Location, namedtuple_to_son
 from .exceptions import ItemNotFoundError
 from .inheritance import own_metadata
 from xmodule.exceptions import InvalidVersionError
+from pytz import UTC
 
 DRAFT = 'draft'
 # Things w/ these categories should never be marked as version='draft'
@@ -197,7 +198,7 @@ class DraftModuleStore(ModuleStoreBase):
         """
         draft = self.get_item(location)
 
-        draft.cms.published_date = datetime.utcnow()
+        draft.cms.published_date = datetime.now(UTC)
         draft.cms.published_by = published_by_id
         super(DraftModuleStore, self).update_item(location, draft._model_data._kvs._data)
         super(DraftModuleStore, self).update_children(location, draft._model_data._kvs._children)
diff --git a/common/lib/xmodule/xmodule/modulestore/xml.py b/common/lib/xmodule/xmodule/modulestore/xml.py
index 4ea83d7e11..6ab6843216 100644
--- a/common/lib/xmodule/xmodule/modulestore/xml.py
+++ b/common/lib/xmodule/xmodule/modulestore/xml.py
@@ -52,7 +52,7 @@ class ImportSystem(XMLParsingSystem, MakoDescriptorSystem):
 
         xmlstore: the XMLModuleStore to store the loaded modules in
         """
-        self.unnamed = defaultdict(int)     # category -> num of new url_names for that category
+        self.unnamed = defaultdict(int)  # category -> num of new url_names for that category
         self.used_names = defaultdict(set)  # category -> set of used url_names
         self.org, self.course, self.url_name = course_id.split('/')
         # cdodge: adding the course_id as passed in for later reference rather than having to recomine the org/course/url_name
@@ -124,7 +124,7 @@ class ImportSystem(XMLParsingSystem, MakoDescriptorSystem):
                     else:
                         # TODO (vshnayder): We may want to enable this once course repos are cleaned up.
                         # (or we may want to give up on the requirement for non-state-relevant issues...)
-                        #error_tracker("WARNING: no name specified for module. xml='{0}...'".format(xml[:100]))
+                        # error_tracker("WARNING: no name specified for module. xml='{0}...'".format(xml[:100]))
                         pass
 
                 # Make sure everything is unique
@@ -447,7 +447,7 @@ class XMLModuleStore(ModuleStoreBase):
     def load_extra_content(self, system, course_descriptor, category, base_dir, course_dir, url_name):
         self._load_extra_content(system, course_descriptor, category, base_dir, course_dir)
 
-         # then look in a override folder based on the course run
+        # then look in a override folder based on the course run
         if os.path.isdir(base_dir / url_name):
             self._load_extra_content(system, course_descriptor, category, base_dir / url_name, course_dir)
 
diff --git a/common/lib/xmodule/xmodule/open_ended_grading_classes/openendedchild.py b/common/lib/xmodule/xmodule/open_ended_grading_classes/openendedchild.py
index 7dc8d99451..b5d4e1b676 100644
--- a/common/lib/xmodule/xmodule/open_ended_grading_classes/openendedchild.py
+++ b/common/lib/xmodule/xmodule/open_ended_grading_classes/openendedchild.py
@@ -16,6 +16,7 @@ from .peer_grading_service import PeerGradingService, MockPeerGradingService
 import controller_query_service
 
 from datetime import datetime
+from django.utils.timezone import UTC
 
 log = logging.getLogger("mitx.courseware")
 
@@ -56,7 +57,7 @@ class OpenEndedChild(object):
     POST_ASSESSMENT = 'post_assessment'
     DONE = 'done'
 
-    #This is used to tell students where they are at in the module
+    # This is used to tell students where they are at in the module
     HUMAN_NAMES = {
         'initial': 'Not started',
         'assessing': 'In progress',
@@ -102,7 +103,7 @@ class OpenEndedChild(object):
         if system.open_ended_grading_interface:
             self.peer_gs = PeerGradingService(system.open_ended_grading_interface, system)
             self.controller_qs = controller_query_service.ControllerQueryService(
-                system.open_ended_grading_interface,system
+                system.open_ended_grading_interface, system
             )
         else:
             self.peer_gs = MockPeerGradingService()
@@ -130,7 +131,7 @@ class OpenEndedChild(object):
         pass
 
     def closed(self):
-        if self.close_date is not None and datetime.utcnow() > self.close_date:
+        if self.close_date is not None and datetime.now(UTC()) > self.close_date:
             return True
         return False
 
@@ -138,13 +139,13 @@ class OpenEndedChild(object):
         if self.closed():
             return True, {
                 'success': False,
-                #This is a student_facing_error
+                # This is a student_facing_error
                 'error': 'The problem close date has passed, and this problem is now closed.'
             }
         elif self.child_attempts > self.max_attempts:
             return True, {
                 'success': False,
-                #This is a student_facing_error
+                # This is a student_facing_error
                 'error': 'You have attempted this problem {0} times.  You are allowed {1} attempts.'.format(
                     self.child_attempts, self.max_attempts
                 )
@@ -272,7 +273,7 @@ class OpenEndedChild(object):
             try:
                 return Progress(int(self.get_score()['score']), int(self._max_score))
             except Exception as err:
-                #This is a dev_facing_error
+                # This is a dev_facing_error
                 log.exception("Got bad progress from open ended child module. Max Score: {0}".format(self._max_score))
                 return None
         return None
@@ -281,10 +282,10 @@ class OpenEndedChild(object):
         """
         return dict out-of-sync error message, and also log.
         """
-        #This is a dev_facing_error
+        # This is a dev_facing_error
         log.warning("Open ended child state out sync. state: %r, get: %r. %s",
                     self.child_state, get, msg)
-        #This is a student_facing_error
+        # This is a student_facing_error
         return {'success': False,
                 'error': 'The problem state got out-of-sync.  Please try reloading the page.'}
 
@@ -391,7 +392,7 @@ class OpenEndedChild(object):
         """
         overall_success = False
         if not self.accept_file_upload:
-            #If the question does not accept file uploads, do not do anything
+            # If the question does not accept file uploads, do not do anything
             return True, get_data
 
         has_file_to_upload, uploaded_to_s3, image_ok, image_tag = self.check_for_image_and_upload(get_data)
@@ -399,19 +400,19 @@ class OpenEndedChild(object):
             get_data['student_answer'] += image_tag
             overall_success = True
         elif has_file_to_upload and not uploaded_to_s3 and image_ok:
-            #In this case, an image was submitted by the student, but the image could not be uploaded to S3.  Likely
-            #a config issue (development vs deployment).  For now, just treat this as a "success"
+            # In this case, an image was submitted by the student, but the image could not be uploaded to S3.  Likely
+            # a config issue (development vs deployment).  For now, just treat this as a "success"
             log.exception("Student AJAX post to combined open ended xmodule indicated that it contained an image, "
                           "but the image was not able to be uploaded to S3.  This could indicate a config"
                           "issue with this deployment, but it could also indicate a problem with S3 or with the"
                           "student image itself.")
             overall_success = True
         elif not has_file_to_upload:
-            #If there is no file to upload, probably the student has embedded the link in the answer text
+            # If there is no file to upload, probably the student has embedded the link in the answer text
             success, get_data['student_answer'] = self.check_for_url_in_text(get_data['student_answer'])
             overall_success = success
 
-        #log.debug("Has file: {0} Uploaded: {1} Image Ok: {2}".format(has_file_to_upload, uploaded_to_s3, image_ok))
+        # log.debug("Has file: {0} Uploaded: {1} Image Ok: {2}".format(has_file_to_upload, uploaded_to_s3, image_ok))
 
         return overall_success, get_data
 
@@ -441,7 +442,7 @@ class OpenEndedChild(object):
         success = False
         allowed_to_submit = True
         response = {}
-        #This is a student_facing_error
+        # This is a student_facing_error
         error_string = ("You need to peer grade {0} more in order to make another submission.  "
                         "You have graded {1}, and {2} are required.  You have made {3} successful peer grading submissions.")
         try:
@@ -451,17 +452,17 @@ class OpenEndedChild(object):
             student_sub_count = response['student_sub_count']
             success = True
         except:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.error("Could not contact external open ended graders for location {0} and student {1}".format(
                 self.location_string, student_id))
-            #This is a student_facing_error
+            # This is a student_facing_error
             error_message = "Could not contact the graders.  Please notify course staff."
             return success, allowed_to_submit, error_message
         if count_graded >= count_required:
             return success, allowed_to_submit, ""
         else:
             allowed_to_submit = False
-            #This is a student_facing_error
+            # This is a student_facing_error
             error_message = error_string.format(count_required - count_graded, count_graded, count_required,
                                                 student_sub_count)
             return success, allowed_to_submit, error_message
diff --git a/common/lib/xmodule/xmodule/peer_grading_module.py b/common/lib/xmodule/xmodule/peer_grading_module.py
index ccc3e31f51..d0d6ef9242 100644
--- a/common/lib/xmodule/xmodule/peer_grading_module.py
+++ b/common/lib/xmodule/xmodule/peer_grading_module.py
@@ -15,6 +15,7 @@ from xmodule.fields import Date, StringyFloat, StringyInteger, StringyBoolean
 
 from xmodule.open_ended_grading_classes.peer_grading_service import PeerGradingService, GradingServiceError, MockPeerGradingService
 from open_ended_grading_classes import combined_open_ended_rubric
+from django.utils.timezone import UTC
 
 log = logging.getLogger(__name__)
 
@@ -76,7 +77,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
     def __init__(self, system, location, descriptor, model_data):
         XModule.__init__(self, system, location, descriptor, model_data)
 
-        #We need to set the location here so the child modules can use it
+        # We need to set the location here so the child modules can use it
         system.set('location', location)
         self.system = system
         if (self.system.open_ended_grading_interface):
@@ -112,7 +113,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
         if not self.ajax_url.endswith("/"):
             self.ajax_url = self.ajax_url + "/"
 
-        #StringyInteger could return None, so keep this check.
+        # StringyInteger could return None, so keep this check.
         if not isinstance(self.max_grade, int):
             raise TypeError("max_grade needs to be an integer.")
 
@@ -120,7 +121,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
         return self._closed(self.timeinfo)
 
     def _closed(self, timeinfo):
-        if timeinfo.close_date is not None and datetime.utcnow() > timeinfo.close_date:
+        if timeinfo.close_date is not None and datetime.now(UTC()) > timeinfo.close_date:
             return True
         return False
 
@@ -166,9 +167,9 @@ class PeerGradingModule(PeerGradingFields, XModule):
         }
 
         if dispatch not in handlers:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.error("Cannot find {0} in handlers in handle_ajax function for open_ended_module.py".format(dispatch))
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             return json.dumps({'error': 'Error handling action.  Please try again.', 'success': False})
 
         d = handlers[dispatch](get)
@@ -187,7 +188,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
             count_required = response['count_required']
             success = True
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("Error getting location data from controller for location {0}, student {1}"
             .format(location, student_id))
 
@@ -220,7 +221,7 @@ class PeerGradingModule(PeerGradingFields, XModule):
             count_graded = response['count_graded']
             count_required = response['count_required']
             if count_required > 0 and count_graded >= count_required:
-                #Ensures that once a student receives a final score for peer grading, that it does not change.
+                # Ensures that once a student receives a final score for peer grading, that it does not change.
                 self.student_data_for_location = response
 
         if self.weight is not None:
@@ -271,10 +272,10 @@ class PeerGradingModule(PeerGradingFields, XModule):
             response = self.peer_gs.get_next_submission(location, grader_id)
             return response
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("Error getting next submission.  server url: {0}  location: {1}, grader_id: {2}"
             .format(self.peer_gs.url, location, grader_id))
-            #This is a student_facing_error
+            # This is a student_facing_error
             return {'success': False,
                     'error': EXTERNAL_GRADER_NO_CONTACT_ERROR}
 
@@ -314,13 +315,13 @@ class PeerGradingModule(PeerGradingFields, XModule):
                                                score, feedback, submission_key, rubric_scores, submission_flagged)
             return response
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("""Error saving grade to open ended grading service.  server url: {0}, location: {1}, submission_id:{2},
                             submission_key: {3}, score: {4}"""
             .format(self.peer_gs.url,
                     location, submission_id, submission_key, score)
             )
-            #This is a student_facing_error
+            # This is a student_facing_error
             return {
                 'success': False,
                 'error': EXTERNAL_GRADER_NO_CONTACT_ERROR
@@ -356,10 +357,10 @@ class PeerGradingModule(PeerGradingFields, XModule):
             response = self.peer_gs.is_student_calibrated(location, grader_id)
             return response
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("Error from open ended grading service.  server url: {0}, grader_id: {0}, location: {1}"
             .format(self.peer_gs.url, grader_id, location))
-            #This is a student_facing_error
+            # This is a student_facing_error
             return {
                 'success': False,
                 'error': EXTERNAL_GRADER_NO_CONTACT_ERROR
@@ -401,17 +402,17 @@ class PeerGradingModule(PeerGradingFields, XModule):
             response = self.peer_gs.show_calibration_essay(location, grader_id)
             return response
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("Error from open ended grading service.  server url: {0}, location: {0}"
             .format(self.peer_gs.url, location))
-            #This is a student_facing_error
+            # This is a student_facing_error
             return {'success': False,
                     'error': EXTERNAL_GRADER_NO_CONTACT_ERROR}
         # if we can't parse the rubric into HTML,
         except etree.XMLSyntaxError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception("Cannot parse rubric string.")
-            #This is a student_facing_error
+            # This is a student_facing_error
             return {'success': False,
                     'error': 'Error displaying submission.  Please notify course staff.'}
 
@@ -455,11 +456,11 @@ class PeerGradingModule(PeerGradingFields, XModule):
                 response['actual_rubric'] = rubric_renderer.render_rubric(response['actual_rubric'])['html']
             return response
         except GradingServiceError:
-            #This is a dev_facing_error
+            # This is a dev_facing_error
             log.exception(
                 "Error saving calibration grade, location: {0}, submission_key: {1}, grader_id: {2}".format(
                     location, submission_key, grader_id))
-            #This is a student_facing_error
+            # This is a student_facing_error
             return self._err_response('There was an error saving your score.  Please notify course staff.')
 
     def peer_grading_closed(self):
@@ -491,13 +492,13 @@ class PeerGradingModule(PeerGradingFields, XModule):
             problem_list = problem_list_dict['problem_list']
 
         except GradingServiceError:
-            #This is a student_facing_error
+            # This is a student_facing_error
             error_text = EXTERNAL_GRADER_NO_CONTACT_ERROR
             log.error(error_text)
             success = False
         # catch error if if the json loads fails
         except ValueError:
-            #This is a student_facing_error
+            # This is a student_facing_error
             error_text = "Could not get list of problems to peer grade.  Please notify course staff."
             log.error(error_text)
             success = False
@@ -557,8 +558,8 @@ class PeerGradingModule(PeerGradingFields, XModule):
         '''
         if get is None or get.get('location') is None:
             if self.use_for_single_location not in TRUE_DICT:
-                #This is an error case, because it must be set to use a single location to be called without get parameters
-                #This is a dev_facing_error
+                # This is an error case, because it must be set to use a single location to be called without get parameters
+                # This is a dev_facing_error
                 log.error(
                     "Peer grading problem in peer_grading_module called with no get parameters, but use_for_single_location is False.")
                 return {'html': "", 'success': False}
diff --git a/common/lib/xmodule/xmodule/tests/test_course_module.py b/common/lib/xmodule/xmodule/tests/test_course_module.py
index 0d789964e9..53181b5a28 100644
--- a/common/lib/xmodule/xmodule/tests/test_course_module.py
+++ b/common/lib/xmodule/xmodule/tests/test_course_module.py
@@ -1,5 +1,4 @@
 import unittest
-from time import strptime
 import datetime
 
 from fs.memoryfs import MemoryFS
@@ -8,13 +7,13 @@ from mock import Mock, patch
 
 from xmodule.modulestore.xml import ImportSystem, XMLModuleStore
 import xmodule.course_module
-from xmodule.util.date_utils import time_to_datetime
+from django.utils.timezone import UTC
 
 
 ORG = 'test_org'
 COURSE = 'test_course'
 
-NOW = strptime('2013-01-01T01:00:00', '%Y-%m-%dT%H:%M:00')
+NOW = datetime.datetime.strptime('2013-01-01T01:00:00', '%Y-%m-%dT%H:%M:00').replace(tzinfo=UTC())
 
 
 class DummySystem(ImportSystem):
@@ -81,10 +80,10 @@ class IsNewCourseTestCase(unittest.TestCase):
             Mock(wraps=datetime.datetime)
         )
         mocked_datetime = datetime_patcher.start()
-        mocked_datetime.utcnow.return_value = time_to_datetime(NOW)
+        mocked_datetime.now.return_value = NOW
         self.addCleanup(datetime_patcher.stop)
 
-    @patch('xmodule.course_module.time.gmtime')
+    @patch('xmodule.course_module.datetime.now')
     def test_sorting_score(self, gmtime_mock):
         gmtime_mock.return_value = NOW
 
@@ -125,7 +124,7 @@ class IsNewCourseTestCase(unittest.TestCase):
             print "Comparing %s to %s" % (a, b)
             assertion(a_score, b_score)
 
-    @patch('xmodule.course_module.time.gmtime')
+    @patch('xmodule.course_module.datetime.now')
     def test_start_date_text(self, gmtime_mock):
         gmtime_mock.return_value = NOW
 
diff --git a/common/lib/xmodule/xmodule/tests/test_date_utils.py b/common/lib/xmodule/xmodule/tests/test_date_utils.py
deleted file mode 100644
index af96de018f..0000000000
--- a/common/lib/xmodule/xmodule/tests/test_date_utils.py
+++ /dev/null
@@ -1,35 +0,0 @@
-# Tests for xmodule.util.date_utils
-
-from nose.tools import assert_equals
-from xmodule.util import date_utils
-import datetime
-import time
-
-
-def test_get_time_struct_display():
-    assert_equals("", date_utils.get_time_struct_display(None, ""))
-    test_time = time.struct_time((1992, 3, 12, 15, 3, 30, 1, 71, 0))
-    assert_equals("03/12/1992", date_utils.get_time_struct_display(test_time, '%m/%d/%Y'))
-    assert_equals("15:03", date_utils.get_time_struct_display(test_time, '%H:%M'))
-
-
-def test_get_default_time_display():
-    assert_equals("", date_utils.get_default_time_display(None))
-    test_time = time.struct_time((1992, 3, 12, 15, 3, 30, 1, 71, 0))
-    assert_equals(
-        "Mar 12, 1992 at 15:03 UTC",
-        date_utils.get_default_time_display(test_time))
-    assert_equals(
-        "Mar 12, 1992 at 15:03 UTC",
-        date_utils.get_default_time_display(test_time, True))
-    assert_equals(
-        "Mar 12, 1992 at 15:03",
-        date_utils.get_default_time_display(test_time, False))
-
-
-def test_time_to_datetime():
-    assert_equals(None, date_utils.time_to_datetime(None))
-    test_time = time.struct_time((1992, 3, 12, 15, 3, 30, 1, 71, 0))
-    assert_equals(
-        datetime.datetime(1992, 3, 12, 15, 3, 30),
-        date_utils.time_to_datetime(test_time))
diff --git a/common/lib/xmodule/xmodule/tests/test_fields.py b/common/lib/xmodule/xmodule/tests/test_fields.py
index 9642f7c595..1b6c86c000 100644
--- a/common/lib/xmodule/xmodule/tests/test_fields.py
+++ b/common/lib/xmodule/xmodule/tests/test_fields.py
@@ -1,24 +1,15 @@
 """Tests for classes defined in fields.py."""
 import datetime
 import unittest
-from django.utils.timezone import UTC
 from xmodule.fields import Date, StringyFloat, StringyInteger, StringyBoolean
-import time
+from django.utils.timezone import UTC
 
 class DateTest(unittest.TestCase):
     date = Date()
 
-    @staticmethod
-    def struct_to_datetime(struct_time):
-        return datetime.datetime(struct_time.tm_year, struct_time.tm_mon,
-            struct_time.tm_mday, struct_time.tm_hour,
-            struct_time.tm_min, struct_time.tm_sec, tzinfo=UTC())
-
-    def compare_dates(self, date1, date2, expected_delta):
-        dt1 = DateTest.struct_to_datetime(date1)
-        dt2 = DateTest.struct_to_datetime(date2)
-        self.assertEqual(dt1 - dt2, expected_delta, str(date1) + "-"
-                                                    + str(date2) + "!=" + str(expected_delta))
+    def compare_dates(self, dt1, dt2, expected_delta):
+        self.assertEqual(dt1 - dt2, expected_delta, str(dt1) + "-"
+                                                    + str(dt2) + "!=" + str(expected_delta))
 
     def test_from_json(self):
         '''Test conversion from iso compatible date strings to struct_time'''
@@ -55,10 +46,10 @@ class DateTest(unittest.TestCase):
     def test_old_due_date_format(self):
         current = datetime.datetime.today()
         self.assertEqual(
-            time.struct_time((current.year, 3, 12, 12, 0, 0, 1, 71, 0)),
+            datetime.datetime(current.year, 3, 12, 12, tzinfo=UTC()),
             DateTest.date.from_json("March 12 12:00"))
         self.assertEqual(
-            time.struct_time((current.year, 12, 4, 16, 30, 0, 2, 338, 0)),
+            datetime.datetime(current.year, 12, 4, 16, 30, tzinfo=UTC()),
             DateTest.date.from_json("December 4 16:30"))
 
     def test_to_json(self):
@@ -67,7 +58,7 @@ class DateTest(unittest.TestCase):
         '''
         self.assertEqual(
             DateTest.date.to_json(
-                time.strptime("2012-12-31T23:59:59Z", "%Y-%m-%dT%H:%M:%SZ")),
+                datetime.datetime.strptime("2012-12-31T23:59:59Z", "%Y-%m-%dT%H:%M:%SZ")),
             "2012-12-31T23:59:59Z")
         self.assertEqual(
             DateTest.date.to_json(
@@ -76,7 +67,7 @@ class DateTest(unittest.TestCase):
         self.assertEqual(
             DateTest.date.to_json(
                 DateTest.date.from_json("2012-12-31T23:00:01-01:00")),
-            "2013-01-01T00:00:01Z")
+            "2012-12-31T23:00:01-01:00")
 
 
 class StringyIntegerTest(unittest.TestCase):
diff --git a/common/lib/xmodule/xmodule/tests/test_import.py b/common/lib/xmodule/xmodule/tests/test_import.py
index bb0d200bb6..677dd4d80e 100644
--- a/common/lib/xmodule/xmodule/tests/test_import.py
+++ b/common/lib/xmodule/xmodule/tests/test_import.py
@@ -13,6 +13,8 @@ from xmodule.modulestore.inheritance import compute_inherited_metadata
 from xmodule.fields import Date
 
 from .test_export import DATA_DIR
+import datetime
+from django.utils.timezone import UTC
 
 ORG = 'test_org'
 COURSE = 'test_course'
@@ -40,7 +42,7 @@ class DummySystem(ImportSystem):
             load_error_modules=load_error_modules,
         )
 
-    def render_template(self, template, context):
+    def render_template(self, _template, _context):
         raise Exception("Shouldn't be called")
 
 
@@ -62,6 +64,7 @@ class BaseCourseTestCase(unittest.TestCase):
 
 
 class ImportTestCase(BaseCourseTestCase):
+    date = Date()
 
     def test_fallback(self):
         '''Check that malformed xml loads as an ErrorDescriptor.'''
@@ -145,15 +148,18 @@ class ImportTestCase(BaseCourseTestCase):
         descriptor = system.process_xml(start_xml)
         compute_inherited_metadata(descriptor)
 
+        # pylint: disable=W0212
         print(descriptor, descriptor._model_data)
-        self.assertEqual(descriptor.lms.due, Date().from_json(v))
+        self.assertEqual(descriptor.lms.due, ImportTestCase.date.from_json(v))
 
         # Check that the child inherits due correctly
         child = descriptor.get_children()[0]
-        self.assertEqual(child.lms.due, Date().from_json(v))
+        self.assertEqual(child.lms.due, ImportTestCase.date.from_json(v))
         self.assertEqual(child._inheritable_metadata, child._inherited_metadata)
         self.assertEqual(2, len(child._inherited_metadata))
-        self.assertEqual('1970-01-01T00:00:00Z', child._inherited_metadata['start'])
+        self.assertLessEqual(ImportTestCase.date.from_json(
+            child._inherited_metadata['start']),
+            datetime.datetime.now(UTC()))
         self.assertEqual(v, child._inherited_metadata['due'])
 
         # Now export and check things
@@ -209,9 +215,13 @@ class ImportTestCase(BaseCourseTestCase):
         # Check that the child does not inherit a value for due
         child = descriptor.get_children()[0]
         self.assertEqual(child.lms.due, None)
+        # pylint: disable=W0212
         self.assertEqual(child._inheritable_metadata, child._inherited_metadata)
         self.assertEqual(1, len(child._inherited_metadata))
-        self.assertEqual('1970-01-01T00:00:00Z', child._inherited_metadata['start'])
+        # why do these tests look in the internal structure v just calling child.start?
+        self.assertLessEqual(
+            ImportTestCase.date.from_json(child._inherited_metadata['start']),
+            datetime.datetime.now(UTC()))
 
     def test_metadata_override_default(self):
         """
@@ -230,14 +240,17 @@ class ImportTestCase(BaseCourseTestCase):
         </course>'''.format(due=course_due, org=ORG, course=COURSE, url_name=url_name)
         descriptor = system.process_xml(start_xml)
         child = descriptor.get_children()[0]
+        # pylint: disable=W0212
         child._model_data['due'] = child_due
         compute_inherited_metadata(descriptor)
 
-        self.assertEqual(descriptor.lms.due, Date().from_json(course_due))
-        self.assertEqual(child.lms.due, Date().from_json(child_due))
+        self.assertEqual(descriptor.lms.due, ImportTestCase.date.from_json(course_due))
+        self.assertEqual(child.lms.due, ImportTestCase.date.from_json(child_due))
         # Test inherited metadata. Due does not appear here (because explicitly set on child).
         self.assertEqual(1, len(child._inherited_metadata))
-        self.assertEqual('1970-01-01T00:00:00Z', child._inherited_metadata['start'])
+        self.assertLessEqual(
+            ImportTestCase.date.from_json(child._inherited_metadata['start']),
+            datetime.datetime.now(UTC()))
         # Test inheritable metadata. This has the course inheritable value for due.
         self.assertEqual(2, len(child._inheritable_metadata))
         self.assertEqual(course_due, child._inheritable_metadata['due'])
diff --git a/common/lib/xmodule/xmodule/timeinfo.py b/common/lib/xmodule/xmodule/timeinfo.py
index a7743b6bee..9a63c0477d 100644
--- a/common/lib/xmodule/xmodule/timeinfo.py
+++ b/common/lib/xmodule/xmodule/timeinfo.py
@@ -1,5 +1,4 @@
 from .timeparse import parse_timedelta
-from xmodule.util.date_utils import time_to_datetime
 
 import logging
 log = logging.getLogger(__name__)
@@ -17,7 +16,7 @@ class TimeInfo(object):
     """
     def __init__(self, due_date, grace_period_string):
         if due_date is not None:
-            self.display_due_date = time_to_datetime(due_date)
+            self.display_due_date = due_date
 
         else:
             self.display_due_date = None
diff --git a/common/lib/xmodule/xmodule/timeparse.py b/common/lib/xmodule/xmodule/timeparse.py
index 15a8233ccb..b189262761 100644
--- a/common/lib/xmodule/xmodule/timeparse.py
+++ b/common/lib/xmodule/xmodule/timeparse.py
@@ -1,9 +1,8 @@
 """
 Helper functions for handling time in the format we like.
 """
-import time
 import re
-from datetime import timedelta
+from datetime import timedelta, datetime
 
 TIME_FORMAT = "%Y-%m-%dT%H:%M"
 
@@ -17,14 +16,14 @@ def parse_time(time_str):
 
     Raises ValueError if the string is not in the right format.
     """
-    return time.strptime(time_str, TIME_FORMAT)
+    return datetime.strptime(time_str, TIME_FORMAT)
 
 
-def stringify_time(time_struct):
+def stringify_time(dt):
     """
-    Convert a time struct to a string
+    Convert a datetime struct to a string
     """
-    return time.strftime(TIME_FORMAT, time_struct)
+    return dt.isoformat()
 
 def parse_timedelta(time_str):
     """
diff --git a/common/lib/xmodule/xmodule/util/date_utils.py b/common/lib/xmodule/xmodule/util/date_utils.py
index 1e64856e8f..050d65fcf1 100644
--- a/common/lib/xmodule/xmodule/util/date_utils.py
+++ b/common/lib/xmodule/xmodule/util/date_utils.py
@@ -1,34 +1,20 @@
-import time
-import datetime
-
-
-def get_default_time_display(time_struct, show_timezone=True):
+def get_default_time_display(dt, show_timezone=True):
     """
-    Converts a time struct to a string representation. This is the default
+    Converts a datetime to a string representation. This is the default
     representation used in Studio and LMS.
     It is of the form "Apr 09, 2013 at 16:00" or "Apr 09, 2013 at 16:00 UTC",
     depending on the value of show_timezone.
 
-    If None is passed in for time_struct, an empty string will be returned.
+    If None is passed in for dt, an empty string will be returned.
     The default value of show_timezone is True.
     """
-    timezone = "" if time_struct is None or not show_timezone else " UTC"
-    return get_time_struct_display(time_struct, "%b %d, %Y at %H:%M") + timezone
-
-
-def get_time_struct_display(time_struct, format):
-    """
-    Converts a time struct to a string based on the given format.
-
-    If None is passed in, an empty string will be returned.
-    """
-    return '' if time_struct is None else time.strftime(format, time_struct)
-
-
-def time_to_datetime(time_struct):
-    """
-    Convert a time struct to a datetime.
-
-    If None is passed in, None will be returned.
-    """
-    return datetime.datetime(*time_struct[:6]) if time_struct else None
+    timezone = ""
+    if dt is not None and show_timezone:
+        if dt.tzinfo is not None:
+            try:
+                timezone = dt.tzinfo.tzname(dt)
+            except NotImplementedError:
+                timezone = " UTC"
+        else:
+            timezone = " UTC"
+    return dt.strftime("%b %d, %Y at %H:%M") + timezone
diff --git a/common/test/data/full/sequential/Administrivia_and_Circuit_Elements.xml b/common/test/data/full/sequential/Administrivia_and_Circuit_Elements.xml
index 47b19f75ed..35e4704d7c 100644
--- a/common/test/data/full/sequential/Administrivia_and_Circuit_Elements.xml
+++ b/common/test/data/full/sequential/Administrivia_and_Circuit_Elements.xml
@@ -1,24 +1,34 @@
 <sequential>
-  <vertical filename="vertical_58" slug="vertical_58" graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted" rerandomize="never"/>
-  <vertical slug="vertical_66" graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted" rerandomize="never">
-    <problem filename="S1E3_AC_power" slug="S1E3_AC_power" name="S1E3: AC power"/>
-    <customtag tag="S1E3" slug="discuss_67" impl="discuss"/>
-    <!-- utf-8 characters acceptable, but not HTML entities -->
-    <html slug="html_68"> S1E4 has been removed…</html>
-  </vertical>
-  <vertical filename="vertical_89" slug="vertical_89" graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted" rerandomize="never"/>
-  <vertical slug="vertical_94" graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted" rerandomize="never">
-    <video youtube="0.75:XNh13VZhThQ,1.0:XbDRmF6J0K0,1.25:JDty12WEQWk,1.50:wELKGj-5iyM" slug="What_s_next" name="What's next"/>
-    <html slug="html_95">Minor correction: Six elements (five resistors)…</html>
-    <customtag tag="S1" slug="discuss_96" impl="discuss"/>
-  </vertical>
+    <vertical filename="vertical_58" slug="vertical_58"
+        graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted"
+        rerandomize="never" />
+    <vertical slug="vertical_66" graceperiod="1 day 12 hours 59 minutes 59 seconds"
+        showanswer="attempted" rerandomize="never">
+        <problem filename="S1E3_AC_power" slug="S1E3_AC_power"
+            name="S1E3: AC power" />
+        <customtag tag="S1E3" slug="discuss_67" impl="discuss" />
+        <!-- utf-8 characters acceptable, but not HTML entities -->
+        <html slug="html_68"> S1E4 has been removed…</html>
+    </vertical>
+    <vertical filename="vertical_89" slug="vertical_89"
+        graceperiod="1 day 12 hours 59 minutes 59 seconds" showanswer="attempted"
+        rerandomize="never" />
+    <vertical slug="vertical_94" graceperiod="1 day 12 hours 59 minutes 59 seconds"
+        showanswer="attempted" rerandomize="never">
+        <video
+            youtube="0.75:XNh13VZhThQ,1.0:XbDRmF6J0K0,1.25:JDty12WEQWk,1.50:wELKGj-5iyM"
+            slug="What_s_next" name="What's next" />
+        <html slug="html_95">Minor correction: Six elements (five resistors)…
+        </html>
+        <customtag tag="S1" slug="discuss_96" impl="discuss" />
+    </vertical>
 
-  <randomize url_name="PS1_Q4" display_name="Problem 4: Read a Molecule">
-    <vertical>
-  <html slug="html_900">
-    <!-- UTF-8 characters are acceptable… HTML entities are not -->
-    <h1>Inline content…</h1>
-  </html>
-</vertical>
-   </randomize>
+    <randomize url_name="PS1_Q4" display_name="Problem 4: Read a Molecule">
+        <vertical>
+            <html slug="html_900">
+                <!-- UTF-8 characters are acceptable… HTML entities are not -->
+                <h1>Inline content…</h1>
+            </html>
+        </vertical>
+    </randomize>
 </sequential>
diff --git a/lms/djangoapps/courseware/access.py b/lms/djangoapps/courseware/access.py
index ace9c0096b..07987a8edf 100644
--- a/lms/djangoapps/courseware/access.py
+++ b/lms/djangoapps/courseware/access.py
@@ -16,6 +16,7 @@ from xmodule.x_module import XModule, XModuleDescriptor
 
 from student.models import CourseEnrollmentAllowed
 from courseware.masquerade import is_masquerading_as_student
+from django.utils.timezone import UTC
 
 DEBUG_ACCESS = False
 
@@ -133,7 +134,7 @@ def _has_access_course_desc(user, course, action):
         (staff can always enroll)
         """
 
-        now = time.gmtime()
+        now = datetime.now(UTC())
         start = course.enrollment_start
         end = course.enrollment_end
 
@@ -242,7 +243,7 @@ def _has_access_descriptor(user, descriptor, action, course_context=None):
 
         # Check start date
         if descriptor.lms.start is not None:
-            now = time.gmtime()
+            now = datetime.now(UTC())
             effective_start = _adjust_start_date_for_beta_testers(user, descriptor)
             if now > effective_start:
                 # after start date, everyone can see it
@@ -365,7 +366,7 @@ def _course_org_staff_group_name(location, course_context=None):
 
 
 def group_names_for(role, location, course_context=None):
-    """Returns the group names for a given role with this location. Plural 
+    """Returns the group names for a given role with this location. Plural
     because it will return both the name we expect now as well as the legacy
     group name we support for backwards compatibility. This should not check
     the DB for existence of a group (like some of its callers do) because that's
@@ -483,8 +484,7 @@ def _adjust_start_date_for_beta_testers(user, descriptor):
        non-None start date.
 
     Returns:
-        A time, in the same format as returned by time.gmtime().  Either the same as
-        start, or earlier for beta testers.
+        A datetime.  Either the same as start, or earlier for beta testers.
 
     NOTE: number of days to adjust should be cached to avoid looking it up thousands of
     times per query.
@@ -505,15 +505,11 @@ def _adjust_start_date_for_beta_testers(user, descriptor):
     beta_group = course_beta_test_group_name(descriptor.location)
     if beta_group in user_groups:
         debug("Adjust start time: user in group %s", beta_group)
-        # time_structs don't support subtraction, so convert to datetimes,
-        # subtract, convert back.
-        # (fun fact: datetime(*a_time_struct[:6]) is the beautiful syntax for
-        # converting time_structs into datetimes)
-        start_as_datetime = datetime(*descriptor.lms.start[:6])
+        start_as_datetime = descriptor.lms.start
         delta = timedelta(descriptor.lms.days_early_for_beta)
         effective = start_as_datetime - delta
         # ...and back to time_struct
-        return effective.timetuple()
+        return effective
 
     return descriptor.lms.start
 
@@ -564,7 +560,7 @@ def _has_access_to_location(user, location, access_level, course_context):
                 return True
         debug("Deny: user not in groups %s", staff_groups)
 
-    if access_level == 'instructor' or access_level == 'staff': 	# instructors get staff privileges
+    if access_level == 'instructor' or access_level == 'staff':  # instructors get staff privileges
         instructor_groups = group_names_for_instructor(location, course_context) + \
                             [_course_org_instructor_group_name(location, course_context)]
         for instructor_group in instructor_groups:
diff --git a/lms/djangoapps/courseware/tests/test_access.py b/lms/djangoapps/courseware/tests/test_access.py
index c1bb9f203e..34d064971f 100644
--- a/lms/djangoapps/courseware/tests/test_access.py
+++ b/lms/djangoapps/courseware/tests/test_access.py
@@ -1,18 +1,12 @@
-import unittest
-import logging
-import time
-from mock import Mock, MagicMock, patch
+from mock import Mock, patch
 
-from django.conf import settings
 from django.test import TestCase
 
-from xmodule.course_module import CourseDescriptor
-from xmodule.error_module import ErrorDescriptor
 from xmodule.modulestore import Location
-from xmodule.timeparse import parse_time
-from xmodule.x_module import XModule, XModuleDescriptor
 import courseware.access as access
 from .factories import CourseEnrollmentAllowedFactory
+import datetime
+from django.utils.timezone import UTC
 
 
 class AccessTestCase(TestCase):
@@ -77,7 +71,7 @@ class AccessTestCase(TestCase):
         # TODO: override DISABLE_START_DATES and test the start date branch of the method
         u = Mock()
         d = Mock()
-        d.start = time.gmtime(time.time() - 86400)   # make sure the start time is in the past
+        d.start = datetime.datetime.now(UTC()) - datetime.timedelta(days=1)  # make sure the start time is in the past
 
         # Always returns true because DISABLE_START_DATES is set in test.py
         self.assertTrue(access._has_access_descriptor(u, d, 'load'))
@@ -85,8 +79,8 @@ class AccessTestCase(TestCase):
 
     def test__has_access_course_desc_can_enroll(self):
         u = Mock()
-        yesterday = time.gmtime(time.time() - 86400)
-        tomorrow = time.gmtime(time.time() + 86400)
+        yesterday = datetime.datetime.now(UTC()) - datetime.timedelta(days=1)
+        tomorrow = datetime.datetime.now(UTC()) + datetime.timedelta(days=1)
         c = Mock(enrollment_start=yesterday, enrollment_end=tomorrow)
 
         # User can enroll if it is between the start and end dates
diff --git a/lms/djangoapps/courseware/tests/tests.py b/lms/djangoapps/courseware/tests/tests.py
index ec3e55b1b8..f037fc6c3e 100644
--- a/lms/djangoapps/courseware/tests/tests.py
+++ b/lms/djangoapps/courseware/tests/tests.py
@@ -3,7 +3,6 @@ Test for lms courseware app
 '''
 import logging
 import json
-import time
 import random
 
 from urlparse import urlsplit, urlunsplit
@@ -30,6 +29,8 @@ from xmodule.modulestore.django import modulestore
 from xmodule.modulestore import Location
 from xmodule.modulestore.xml_importer import import_from_xml
 from xmodule.modulestore.xml import XMLModuleStore
+import datetime
+from django.utils.timezone import UTC
 
 log = logging.getLogger("mitx." + __name__)
 
@@ -603,9 +604,9 @@ class TestViewAuth(LoginEnrollmentTestCase):
         """Actually do the test, relying on settings to be right."""
 
         # Make courses start in the future
-        tomorrow = time.time() + 24 * 3600
-        self.toy.lms.start = time.gmtime(tomorrow)
-        self.full.lms.start = time.gmtime(tomorrow)
+        tomorrow = datetime.datetime.now(UTC()) + datetime.timedelta(days=1)
+        self.toy.lms.start = tomorrow
+        self.full.lms.start = tomorrow
 
         self.assertFalse(self.toy.has_started())
         self.assertFalse(self.full.has_started())
@@ -728,18 +729,18 @@ class TestViewAuth(LoginEnrollmentTestCase):
         """Actually do the test, relying on settings to be right."""
 
         # Make courses start in the future
-        tomorrow = time.time() + 24 * 3600
-        nextday = tomorrow + 24 * 3600
-        yesterday = time.time() - 24 * 3600
+        tomorrow = datetime.datetime.now(UTC()) + datetime.timedelta(days=1)
+        nextday = tomorrow + datetime.timedelta(days=1)
+        yesterday = datetime.datetime.now(UTC()) - datetime.timedelta(days=1)
 
         print "changing"
         # toy course's enrollment period hasn't started
-        self.toy.enrollment_start = time.gmtime(tomorrow)
-        self.toy.enrollment_end = time.gmtime(nextday)
+        self.toy.enrollment_start = tomorrow
+        self.toy.enrollment_end = nextday
 
         # full course's has
-        self.full.enrollment_start = time.gmtime(yesterday)
-        self.full.enrollment_end = time.gmtime(tomorrow)
+        self.full.enrollment_start = yesterday
+        self.full.enrollment_end = tomorrow
 
         print "login"
         # First, try with an enrolled student
@@ -778,12 +779,10 @@ class TestViewAuth(LoginEnrollmentTestCase):
         self.assertFalse(settings.MITX_FEATURES['DISABLE_START_DATES'])
 
         # Make courses start in the future
-        tomorrow = time.time() + 24 * 3600
-        # nextday = tomorrow + 24 * 3600
-        # yesterday = time.time() - 24 * 3600
+        tomorrow = datetime.datetime.now(UTC()) + datetime.timedelta(days=1)
 
         # toy course's hasn't started
-        self.toy.lms.start = time.gmtime(tomorrow)
+        self.toy.lms.start = tomorrow
         self.assertFalse(self.toy.has_started())
 
         # but should be accessible for beta testers
@@ -854,7 +853,7 @@ class TestSubmittingProblems(LoginEnrollmentTestCase):
         modx_url = self.modx_url(problem_location, 'problem_check')
         answer_key_prefix = 'input_i4x-edX-{}-problem-{}_'.format(self.course_slug, problem_url_name)
         resp = self.client.post(modx_url,
-            { (answer_key_prefix + k): v for k,v in responses.items() }
+            { (answer_key_prefix + k): v for k, v in responses.items() }
             )
         return resp
 
@@ -925,7 +924,7 @@ class TestCourseGrader(TestSubmittingProblems):
         # Only get half of the first problem correct
         self.submit_question_answer('H1P1', {'2_1': 'Correct', '2_2': 'Incorrect'})
         self.check_grade_percent(0.06)
-        self.assertEqual(earned_hw_scores(), [1.0, 0, 0])   # Order matters
+        self.assertEqual(earned_hw_scores(), [1.0, 0, 0])  # Order matters
         self.assertEqual(score_for_hw('Homework1'), [1.0, 0.0])
 
         # Get both parts of the first problem correct
@@ -958,16 +957,16 @@ class TestCourseGrader(TestSubmittingProblems):
 
         # Third homework
         self.submit_question_answer('H3P1', {'2_1': 'Correct', '2_2': 'Correct'})
-        self.check_grade_percent(0.42)   # Score didn't change
+        self.check_grade_percent(0.42)  # Score didn't change
         self.assertEqual(earned_hw_scores(), [4.0, 4.0, 2.0])
 
         self.submit_question_answer('H3P2', {'2_1': 'Correct', '2_2': 'Correct'})
-        self.check_grade_percent(0.5)   # Now homework2 dropped. Score changes
+        self.check_grade_percent(0.5)  # Now homework2 dropped. Score changes
         self.assertEqual(earned_hw_scores(), [4.0, 4.0, 4.0])
 
         # Now we answer the final question (worth half of the grade)
         self.submit_question_answer('FinalQuestion', {'2_1': 'Correct', '2_2': 'Correct'})
-        self.check_grade_percent(1.0)   # Hooray! We got 100%
+        self.check_grade_percent(1.0)  # Hooray! We got 100%
 
 
 @override_settings(MODULESTORE=TEST_DATA_XML_MODULESTORE)
@@ -1000,7 +999,7 @@ class TestSchematicResponse(TestSubmittingProblems):
             { '2_1': json.dumps(
                 [['transient', {'Z': [
                 [0.0000004, 2.8],
-                [0.0000009, 0.0],       # wrong.
+                [0.0000009, 0.0],  # wrong.
                 [0.0000014, 2.8],
                 [0.0000019, 2.8],
                 [0.0000024, 2.8],
diff --git a/lms/djangoapps/django_comment_client/utils.py b/lms/djangoapps/django_comment_client/utils.py
index 276956f0e9..007a8fedfd 100644
--- a/lms/djangoapps/django_comment_client/utils.py
+++ b/lms/djangoapps/django_comment_client/utils.py
@@ -1,14 +1,9 @@
-import time
 from collections import defaultdict
 import logging
-import time
 import urllib
 from datetime import datetime
 
 from courseware.module_render import get_module
-from xmodule.modulestore import Location
-from xmodule.modulestore.django import modulestore
-from xmodule.modulestore.search import path_to_location
 from django.contrib.auth.models import User
 from django.core.urlresolvers import reverse
 from django.db import connection
@@ -16,13 +11,12 @@ from django.http import HttpResponse
 from django.utils import simplejson
 from django_comment_common.models import Role
 from django_comment_client.permissions import check_permissions_by_view
-from xmodule.modulestore.exceptions import NoPathToItem
 
 from mitxmako import middleware
 import pystache_custom as pystache
 
-from xmodule.modulestore import Location
 from xmodule.modulestore.django import modulestore
+from django.utils.timezone import UTC
 
 log = logging.getLogger(__name__)
 
@@ -100,7 +94,7 @@ def get_discussion_category_map(course):
 
 def filter_unstarted_categories(category_map):
 
-    now = time.gmtime()
+    now = datetime.now(UTC())
 
     result_map = {}
 
@@ -220,7 +214,7 @@ def initialize_discussion_info(course):
     for topic, entry in course.discussion_topics.items():
         category_map['entries'][topic] = {"id": entry["id"],
                                           "sort_key": entry.get("sort_key", topic),
-                                          "start_date": time.gmtime()}
+                                          "start_date": datetime.now(UTC())}
     sort_map_entries(category_map)
 
     _DISCUSSIONINFO[course.id]['id_map'] = discussion_id_map
@@ -292,7 +286,7 @@ def get_ability(course_id, content, user):
         'can_vote': check_permissions_by_view(user, course_id, content, "vote_for_thread" if content['type'] == 'thread' else "vote_for_comment"),
     }
 
-#TODO: RENAME
+# TODO: RENAME
 
 
 def get_annotated_content_info(course_id, content, user, user_info):
@@ -310,7 +304,7 @@ def get_annotated_content_info(course_id, content, user, user_info):
         'ability': get_ability(course_id, content, user),
     }
 
-#TODO: RENAME
+# TODO: RENAME
 
 
 def get_annotated_content_infos(course_id, thread, user, user_info):