You can delete your classes, but you can also re-use them -- I have moved students from "active" classes to "archive" classes that have students that I do not currently teach anymore. This will all...

1. Közösség
2. Classroom Tips and Tricks
3. OHQ Archiving classes & progress tab for art history

A lesson per day is very doable, especially if you will be expecting students to work outside of the classroom on Khan.  Remember to be flexible and differentiate the lessons for your students. 

1. Közösség
2. Classroom Tips and Tricks
3. Pacing lessons in Khan