Is there a way I can re-set the lessons all at once?

Is there a way I can re-set the lessons all at once? It is very time consuming to have to go back and re-set each lesson to the original version when you teach the same lesson multiple times a day.

Are you talking about resetting the code version in the bubbles? I don’t think it is possible to do all at once. It would be a good feature request which you can make by writing to support@code.org.