When you execute the rails scaffold command, this is the output you can expect:
$ bin/rails generate scaffold HighScore game:string score:integer
invoke active_record
create db/migrate/20130717151933_create_high_scores.rb
create app/models/high_score.rb
invoke test_unit
create test/models/high_score_test.rb
create test/fixtures/high_scores.yml
invoke resource_route
route resources :high_scores
invoke scaffold_controller
create app/controllers/high_scores_controller.rb
invoke erb
create app/views/high_scores
create app/views/high_scores/index.html.erb
create app/views/high_scores/edit.html.erb
create app/views/high_scores/show.html.erb
create app/views/high_scores/new.html.erb
create app/views/high_scores/_form.html.erb
invoke test_unit
create test/controllers/high_scores_controller_test.rb
invoke helper
create app/helpers/high_scores_helper.rb
invoke jbuilder
create app/views/high_scores/index.json.jbuilder
create app/views/high_scores/show.json.jbuilder
invoke assets
invoke coffee
create app/assets/javascripts/high_scores.coffee
invoke scss
create app/assets/stylesheets/high_scores.scss
invoke scss
identical app/assets/stylesheets/scaffolds.scss
Note that Rails generates a scaffolds.scss file and another one specifically for your model. By default, the model's stylesheet does not have CSS rules, while the scaffold stylesheet does. You may consider deleting the unneeded scaffold stylesheet.
If you wish to avoid generating unnecessary CSS files, you can use the --no-stylesheets or --no-scaffold-stylesheet flags.