As TAs you have the same features available to you as the professor, your access will just end when the semester closes, so please peruse the Instructor help pages for all the classics, like:
Assignment solutions
Question Search (and bulk exporting/importing questions)
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Communicating with Students: you can post class announcements, or if you need to just let a few students know something, you can grab their email off the roster (on the left side bar). This could take a few steps out using Canvas as the communication run around.
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