How do i tell the check_box method to NOT add a hidden check_box for the 'unchecked' value?

In Rails 4 you can use include_hidden: false

example f.check_box :some_field, include_hidden: false

Since Rails 3.2, the hidden field will not be shown if the unchecked_value argument evaluates to false.

Example: f.check_box :your_field, {}, checked_value, false

See the Rails source: 3.2, 4.1

use <%= check_box_tag "your_model[your_field]" %>

f.check_box always gives you a hidden field.