diff --git a/src/logic/course.ts b/src/logic/course.ts
index 045235c..3a264d9 100644
--- a/src/logic/course.ts
+++ b/src/logic/course.ts
@@ -29,6 +29,9 @@ export class Assignment
 
     gradingPeriod: number;
 
+    // Callbacks when this object updates
+    private updateCallbacks: (() => void)[] = [];
+
     /**
      * Construct assignment with json object
      *