diff --git a/app/models/attribute.rb b/app/models/attribute.rb
index af0710be3bf389b3fec994e82629afaccbc4e199..403de827e79c89db129ffb655cd0e36587ad9c0b 100644
--- a/app/models/attribute.rb
+++ b/app/models/attribute.rb
@@ -1,6 +1,6 @@
 class Attribute
   include ActiveModel::Model
+  include OrientDbSerializable
 
   attr_accessor :id, :key, :value
-  
 end
\ No newline at end of file
diff --git a/app/repositories/orient_db/attribute_repository.rb b/app/repositories/orient_db/attribute_repository.rb
index a0283b36a4f8bd77f59550110429e634ba30b732..6d05df8a8d3a94746306c105d8acc2d21329c356 100644
--- a/app/repositories/orient_db/attribute_repository.rb
+++ b/app/repositories/orient_db/attribute_repository.rb
@@ -13,6 +13,8 @@ module OrientDb
       build_objects get_edges_end("HasAttr", "out", learning_object.id)
     end
 
+    protected
+
     def build_object(args={})
       AttributeBuilder.build_from_orientdb args
     end