I also am a teacher starting in a new area this year. I've been in a regular classroom for 22 years and am going to start teaching music this year. It's like starting all over again. I will have kindergarten through 5th grade students every day. I am right there with you on being too tired to do anything but hit the couch at the end of the day. I hope your year goes well and you are able to squeeze in some fun stuff after school starts.