no, call <%= yield %>

railties/lib/rails/generators/rails/app/templates/README

@@ -220,7 +220,7 @@ app/views/layouts
   Holds the template files for layouts to be used with views. This models the
   common header/footer method of wrapping views. In your views, define a layout
   using the <tt>layout :default</tt> and create a file named default.html.erb.
-  Inside default.html.erb, call <% yield %> to render the view using this
+  Inside default.html.erb, call <%= yield %> to render the view using this
   layout.
 
 app/helpers