Hi ksaldutti,

Currently, there is not a functionality to add a co-teacher or two teachers to one class. This has been a popular suggestion though, so it could possibly be implemented sometime in the future.

There are still ways for multiple teachers to see student's progress - this article can explain more, and provide suggestions on how they can have access to student's progress: https://khanacademy.zendesk.com/hc/en-us/articles/203610350-Can-a-user-have-multiple-coaches-Is-there-a-way-to-add-a-co-teacher-.

Hope this helps! Please let me know if you have any further questions!