On some non-form pages, I have a few links that would look better as a button than a hyperlink...
I thought button_to instead of link_to would work, but buton_to see
I think all you want here is the just view. and if that is the case then you can just add a class to the class object in link
<%= link_to 'Add Class', new_subject_path, class: "btn btn-primary"%>