That's about how long it took me to get used to teaching six graders, and I was only doing it one night a week at our church. Man, those first two years sucked, but I learned from it.
Call me insane, but I'm finishing up my 20th year. Now that I've left the rat race, I'll do some substitute teaching next school year, at the request of our ISD's superintendent. We've known each other about 20 years, as he was in a variety of positions as my kids went through school.
It's tough to bring it every day, but kids are more attentive when the teacher is engaged and enthusiastic. At least, that's been my experience, and I've done it with class sizes as large as 30 raucous 12 YO's.
Do you have your concealed carry weapon picked out yet?