diff --git a/bases/rsptx/book_server_api/routers/course.py b/bases/rsptx/book_server_api/routers/course.py
index 2cba97469..e487b2a9e 100644
--- a/bases/rsptx/book_server_api/routers/course.py
+++ b/bases/rsptx/book_server_api/routers/course.py
@@ -171,7 +171,7 @@ def sort_key(assignment):
             "student_page": True,
             "course_list": course_list,
             "is_instructor": "true" if user_is_instructor else "false",
-            "has_discussion_group": book.social_url,
+            "has_discussion_group": book.social_url if book else None,
             "lti1p1": is_lti1p1_course,
             "now": now,
             "visibility_map": visibility_map,