I noticed that the class was created and publiclly available before I finished adding all of the class details. It might be nice to let the user add all of the class details before it is goes live. Not a big hangup but could be a subtle improvement. Great site BTW. Love the ease of use and simple (yet sophisticated) interface. Can tell that you guys have spent some time doing your usability homework!

I would recommend polling your teachers and asking them if they would like to have videos on their class descriptions or profiles. Sometimes seeing a teacher can be a great way to know if they will be a good fit and it will make it much more interactive on the site. I would personally check out the pages just to look at the videos!