Fix

app/controllers/learning_objects_controller.rb

@@ -112,7 +112,7 @@ class LearningObjectsController < ApplicationController
 
   def build_subjects(subjects)
     subjects.map do |subject|
-      subject_repository.find subject
+      Topic.find subject
     end
   end
 

app/controllers/search_controller.rb

 class SearchController < ApplicationController
   def index
-    @types = learning_object_repository.types
+    @types = LearningObject.default_types
 
     @subjects = Topic.default_list