diff --git a/common/djangoapps/student/migrations/0039_anon_id_context.py b/common/djangoapps/student/migrations/0039_anon_id_context.py
new file mode 100644
index 0000000000..f241d3623c
--- /dev/null
+++ b/common/djangoapps/student/migrations/0039_anon_id_context.py
@@ -0,0 +1,30 @@
+# Convert the student.models.AnonymousUserId.course_id field from CourseKey to
+# the more generic LearningContextKey.
+#
+# This migration does not produce any changes at the database level.
+
+from django.db import migrations
+import opaque_keys.edx.django.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('student', '0038_auto_20201021_1256'),
+    ]
+
+    operations = [
+        migrations.SeparateDatabaseAndState(
+            # Do not actually make any changes to the database; the fields are identical string fields with the same
+            # database properties.
+            database_operations=[],
+            # But update the migrator's view of the field to reflect the new field type.
+            state_operations=[
+                migrations.AlterField(
+                    model_name='anonymoususerid',
+                    name='course_id',
+                    field=opaque_keys.edx.django.models.LearningContextKeyField(blank=True, db_index=True, max_length=255),
+                ),
+            ],
+        ),
+    ]
diff --git a/common/djangoapps/student/models.py b/common/djangoapps/student/models.py
index 2c58927ee9..15c8c7ec78 100644
--- a/common/djangoapps/student/models.py
+++ b/common/djangoapps/student/models.py
@@ -46,7 +46,7 @@ from edx_django_utils.cache import RequestCache
 from edx_rest_api_client.exceptions import SlumberBaseException
 from eventtracking import tracker
 from model_utils.models import TimeStampedModel
-from opaque_keys.edx.django.models import CourseKeyField
+from opaque_keys.edx.django.models import CourseKeyField, LearningContextKeyField
 from opaque_keys.edx.keys import CourseKey
 from pytz import UTC
 from simple_history.models import HistoricalRecords
@@ -143,7 +143,7 @@ class AnonymousUserId(models.Model):
 
     user = models.ForeignKey(User, db_index=True, on_delete=models.CASCADE)
     anonymous_user_id = models.CharField(unique=True, max_length=32)
-    course_id = CourseKeyField(db_index=True, max_length=255, blank=True)
+    course_id = LearningContextKeyField(db_index=True, max_length=255, blank=True)
 
 
 def anonymous_id_for_user(user, course_id, save=True):
diff --git a/openedx/core/djangoapps/xblock/runtime/shims.py b/openedx/core/djangoapps/xblock/runtime/shims.py
index a5afd95357..0cc43b6cff 100644
--- a/openedx/core/djangoapps/xblock/runtime/shims.py
+++ b/openedx/core/djangoapps/xblock/runtime/shims.py
@@ -3,7 +3,6 @@ Code to implement backwards compatibility
 """
 # pylint: disable=no-member
 
-import hashlib
 import warnings
 
 from django.conf import settings
@@ -12,9 +11,9 @@ from django.template import TemplateDoesNotExist
 from django.utils.functional import cached_property
 from fs.memoryfs import MemoryFS
 from openedx.core.djangoapps.xblock.apps import get_xblock_app_config
-import six
 
 from common.djangoapps.edxmako.shortcuts import render_to_string
+from common.djangoapps.student.models import anonymous_id_for_user
 
 
 class RuntimeShim(object):
@@ -71,19 +70,8 @@ class RuntimeShim(object):
             # really care since this user's XBlock data is ephemeral and is only
             # kept around for a day or two anyways.
             return self.user_id
-        #### TEMPORARY IMPLEMENTATION:
-        # TODO: Update student.models.AnonymousUserId to have a 'context_key'
-        # column instead of 'course_key' (no DB migration needed). Then change
-        # this to point to the existing student.models.anonymous_id_for_user
-        # code. (Or do we want a separate new table for the new runtime?)
-        # The reason we can't do this now is that ContextKey doesn't yet exist
-        # in the opaque-keys repo, so there is no working 'ContextKeyField'
-        # class in opaque-keys that accepts either old CourseKeys or new
-        # LearningContextKeys.
-        hasher = hashlib.md5()
-        hasher.update(settings.SECRET_KEY.encode('utf-8'))
-        hasher.update(six.text_type(self.user_id).encode('utf-8'))
-        digest = hasher.hexdigest()
+        context_key = self._active_block.scope_ids.usage_id.context_key
+        digest = anonymous_id_for_user(self.user, course_id=context_key)
         return digest
 
     @property