You should set up seperate top level controllers to inherit from to prevent the skipping. That is going to get very confusing soon.
```ruby
def AdminBaseController < ApplicationController
  before_filter :authenticate_admin
end

def Admin::OtherController < AdminBaseController
end

def InstructorBaseController < ApplicationController
  before_filter :authenticate_teacher!
end
 
def Instructor::SectionsController < InstructorsBaseController
end
```