Assuming you don't mean copying or distributing the files, you're welcome to use any of our free/ non-premium videos to assist in your teaching without any stipulations.
For premium content, as long as you're not sharing your log-in information for someone to access your premium account while not in your presence, you may show the videos to your student(s) during a lesson to assist in your teaching. We hope that you will encourage your students to support our website by creating their own user accounts and signing up for premium membership to help them with their off-lesson studies. You could remind them that a premium membership gives them access to videos through full silver in 22 dances for the cost equivalent of about 1-2 private lessons.
Thank you for asking!
Regards,
Jonathan Atkinson
www.ballroomdancers.com