title: Ruby on Rails Dynamic forms
body: <p>I have a week model (has_many days) and days model (belongs_to week), initially I generate a form that has 7 days. </p>
  
  <p>Each day has some inputs (class name and description), I want to add a feature where user can add more lass name and descriptions dynamically. Do I need to create another model to hold these attributes or there is another way to handle that? </p>
  
  <p>I was thinking about using cocoon and  just add days dynamically. Any recommendations?
  I use rails 4 and ruby 2.</p>