You might want to try working at one specific school and see if you can be both an elementary and middle school teacher (maybe 2-3 years each, depends how long you want to teach)
However, I agree with all the other comments about how middle school is easiest, (and probably most pleasing for you) to teach.
however, from a student point of view, having a good -or at least, comprehensible- teacher in highschool is practically essential. I have a maths teacher who can't explain concepts well to the entire class, and many students are now suffering in their maths work. It's at this point, when you are close to applying for college and university, that students really need a good teacher. (Actually another critical point in teaching is making sure kids learn how to properly read and write letters and numbers, so I would also advise kindergarten) Both Kindergarten and High school teaching can be a challenge, but if you think you're up for it, then go for it!
p.s the math teacher is a really nice lady and all, but we aren't so sure what comes out of her mouth 50% of the time...