Today kicked my butt

The host teacher was out because of jury duty and I had a sub in the room. So, I was in charge of the class really- she's there to make sure I don't, you know, injure a child or something. The kids weren't horrible, but the talking out and talking over me was ridiculous! We only got half of Language Arts done. They bombed the Social Studies assignments. Which may be a testanment to my teaching of the lessons rather than the students abilities. We had a crazy schedule because of an assembly. And to top it off I sent a student home on the bus without a note from the parent. Luckily, that really was what he was supposed to do today. I was left feeling completely defeated. I feel better after talking to my host teacher on the phone today. Can I have a do-over?