Can you really not stand it for 6 months? That really isn't very long, barely till next fall. Are you being physically threatened or abused?
Almost all jobs are difficult. Is there anything you can negotiate with your manager, or with the other teachers you work with? Sometimes things seem really hard, bad, gloomy and as if there is no way out. "When will this nightmare ever end?!"
Do you have friends, places you like to go, things to do on your days off? Where ever I go, I find a place that feels a bit homey to me, that I'm comfortable going to, a place that I would go to at home. After a couple of hours or so there on a day off, I'm usually feeling much better about things.
Maybe doing this is more of a lesson in something you haven't discovered you need to learn. Or maybe its just another lesson in how to cope, be patient, be creative.
And THAT being said, I felt I had to leave early in my last job. But I cant think of a more incompetent manager than the last two I've had.
Good luck and tell us what you decide.