The best and the worst.
Worst: Trying to figure out how to teach a Math Unit that I myself did not understand. UGHH
Having my supervisor say you need to talk faster I can tell it is part of your personality but you are gonna put those kids to sleep.
The best has been small groups or one on one sessions, when I have actually been able to see the light go on in their heads. It has been much easier to connect to them one on one.