diff --git a/conftest.py b/conftest.py
index 3fc522a9692c..f1bcb2c66d08 100644
--- a/conftest.py
+++ b/conftest.py
@@ -15,3 +15,41 @@
 # When using self.assertEquals, diffs are truncated. We don't want that, always
 # show the whole diff.
 TestCase.maxDiff = None
+
+
+@pytest.fixture(autouse=True)
+def create_edxnotes_oauth_client(request):
+    """
+    Create edx-notes OAuth2 Application for tests that have DB access
+    when ENABLE_EDXNOTES is enabled.
+    """
+    from django.test import TransactionTestCase
+
+    # Only run for Django class-based tests with DB access.
+    if not request.cls:
+        return
+    if not issubclass(request.cls, TransactionTestCase):
+        return
+
+    # Skip for edxnotes tests; they create their own Application.
+    if 'edxnotes' in request.node.module.__name__:
+        return
+
+    from django.conf import settings
+
+    client_name = getattr(settings, 'EDXNOTES_CLIENT_NAME', None)
+    if not client_name:
+        return
+
+    if not getattr(settings, 'FEATURES', {}).get('ENABLE_EDXNOTES', False):
+        return
+
+    from oauth2_provider.models import Application
+
+    if not Application.objects.filter(name=client_name).exists():
+        Application.objects.create(
+            name=client_name,
+            user=None,
+            client_type=Application.CLIENT_CONFIDENTIAL,
+            authorization_grant_type=Application.GRANT_CLIENT_CREDENTIALS,
+        )
diff --git a/openedx/core/djangoapps/course_apps/tests/test_notes_app.py b/openedx/core/djangoapps/course_apps/tests/test_notes_app.py
index db2d3563b821..c8c677125b51 100644
--- a/openedx/core/djangoapps/course_apps/tests/test_notes_app.py
+++ b/openedx/core/djangoapps/course_apps/tests/test_notes_app.py
@@ -19,6 +19,12 @@ class NotesCourseAppTestCase(TabBasedCourseAppTestMixin, ModuleStoreTestCase):
     tab_type = 'edxnotes'
     course_app_class = EdxNotesCourseApp
 
+    def test_app_disabled_by_default(self):
+        """
+        Override base mixin behavior: Notes is enabled by default.
+        """
+        assert self.course_app_class.is_enabled(self.course.id)
+
     def _assert_app_enabled(self, app_tab):
         assert app_tab.is_enabled(self.course, self.user)
 
diff --git a/xmodule/modulestore/inheritance.py b/xmodule/modulestore/inheritance.py
index 4c5a14b769cb..f34256777c46 100644
--- a/xmodule/modulestore/inheritance.py
+++ b/xmodule/modulestore/inheritance.py
@@ -210,7 +210,7 @@ class InheritanceMixin(XBlockMixin):
     edxnotes = Boolean(
         display_name=_("Enable Student Notes"),
         help=_("Enter true or false. If true, students can use the Student Notes feature."),
-        default=False,
+        default=True,
         scope=Scope.settings
     )
     edxnotes_visibility = Boolean(
diff --git a/xmodule/tests/test_split_test_block.py b/xmodule/tests/test_split_test_block.py
index c51c157a7760..6cca4701b18b 100644
--- a/xmodule/tests/test_split_test_block.py
+++ b/xmodule/tests/test_split_test_block.py
@@ -123,6 +123,7 @@ def setUp(self):
         self.split_test_block.runtime.modulestore = mocked_modulestore
 
 
+@patch.dict("django.conf.settings.FEATURES", {"ENABLE_EDXNOTES": False})
 @ddt.ddt
 class SplitTestBlockLMSTest(SplitTestBlockTest):
     """
@@ -186,6 +187,7 @@ def test_export_import_round_trip(self, def_to_xml):
         assert len(children) == 2
 
 
+@patch.dict("django.conf.settings.FEATURES", {"ENABLE_EDXNOTES": False})
 class SplitTestBlockStudioTest(SplitTestBlockTest):
     """
     Unit tests for how split test interacts with Studio.