diff --git a/railties/lib/rails/generators/active_model.rb b/railties/lib/rails/generators/active_model.rb
index e5373704d7..71104a069c 100644
--- a/railties/lib/rails/generators/active_model.rb
+++ b/railties/lib/rails/generators/active_model.rb
@@ -34,7 +34,7 @@ def initialize(name)
 
       # GET index
       def self.all(klass)
-        "#{klass}.all"
+        "#{klass}.all.to_a"
       end
 
       # GET show