diff --git a/cms/djangoapps/models/settings/course_grading.py b/cms/djangoapps/models/settings/course_grading.py
index 36f5e4cb97..b20fb71f66 100644
--- a/cms/djangoapps/models/settings/course_grading.py
+++ b/cms/djangoapps/models/settings/course_grading.py
@@ -213,7 +213,7 @@ class CourseGradingModel(object):
 
         descriptor = get_modulestore(location).get_item(location)
         return {
-                "graderType": descriptor.lms.format or 'Not Graded',
+                "graderType": descriptor.lms.format if descriptor.lms.format is not None else 'Not Graded',
                 "location": location,
                 "id": 99   # just an arbitrary value to
                 }
diff --git a/cms/templates/edit_subsection.html b/cms/templates/edit_subsection.html
index 68e9d2f8e4..42ddc39be1 100644
--- a/cms/templates/edit_subsection.html
+++ b/cms/templates/edit_subsection.html
@@ -70,7 +70,7 @@
     <div class="row gradable">
       <label>Graded as:</label>
 
-    <div class="gradable-status" data-initial-status="${subsection.lms.format if subsection.lms.format is None else 'Not Graded'}">
+    <div class="gradable-status" data-initial-status="${subsection.lms.format if subsection.lms.format is not None else 'Not Graded'}">
     </div>
 
     <div class="due-date-input row">
diff --git a/common/lib/xmodule/xmodule/course_module.py b/common/lib/xmodule/xmodule/course_module.py
index 627e9ab8de..9c757d0ac6 100644
--- a/common/lib/xmodule/xmodule/course_module.py
+++ b/common/lib/xmodule/xmodule/course_module.py
@@ -592,7 +592,7 @@ class CourseDescriptor(SequenceDescriptor):
                     # The xmoduledescriptors included here are only the ones that have scores.
                     section_description = {'section_descriptor': s, 'xmoduledescriptors': filter(lambda child: child.has_score, xmoduledescriptors)}
 
-                    section_format = s.lms.format
+                    section_format = s.lms.format if s.lms.format is not None else ''
                     graded_sections[section_format] = graded_sections.get(section_format, []) + [section_description]
 
                     all_descriptors.extend(xmoduledescriptors)
diff --git a/lms/djangoapps/courseware/grades.py b/lms/djangoapps/courseware/grades.py
index eab612e34a..f9982db8fe 100644
--- a/lms/djangoapps/courseware/grades.py
+++ b/lms/djangoapps/courseware/grades.py
@@ -317,7 +317,7 @@ def progress_summary(student, request, course, model_data_cache):
             section_total, graded_total = graders.aggregate_scores(
                 scores, section_module.display_name_with_default)
 
-            format = section_module.lms.format
+            format = section_module.lms.format if section_module.lms.format is not None else ''
             sections.append({
                 'display_name': section_module.display_name_with_default,
                 'url_name': section_module.url_name,
diff --git a/lms/djangoapps/courseware/module_render.py b/lms/djangoapps/courseware/module_render.py
index 8a4796ed15..5ef7dff421 100644
--- a/lms/djangoapps/courseware/module_render.py
+++ b/lms/djangoapps/courseware/module_render.py
@@ -103,7 +103,7 @@ def toc_for_course(user, request, course, active_chapter, active_section, model_
             if not section.lms.hide_from_toc:
                 sections.append({'display_name': section.display_name_with_default,
                                  'url_name': section.url_name,
-                                 'format': section.lms.format,
+                                 'format': section.lms.format if section.lms.format is not None else '',
                                  'due': section.lms.due,
                                  'active': active,
                                  'graded': section.lms.graded,
diff --git a/lms/xmodule_namespace.py b/lms/xmodule_namespace.py
index 191859379c..a641947a0e 100644
--- a/lms/xmodule_namespace.py
+++ b/lms/xmodule_namespace.py
@@ -24,7 +24,6 @@ class LmsNamespace(Namespace):
         help="What format this module is in (used for deciding which "
              "grader to apply, and what to show in the TOC)",
         scope=Scope.settings,
-        default='',
     )
 
     start = Date(help="Start time when this module is visible", scope=Scope.settings)