There are other on-line schools besides Phoenix. Nova Southeastern and Walden are two, though I’m not sure if they offer a Masters in math. Both have websites where you can check their offerings.

If you want to be a coach, perhaps you can get a second bachelors in education with a physical education focus. That would put you in good stead for a coaching position. Again, it will take some homework on your part to find a school with that program. Or a second bachelors in education with a focus on math would be an alternative. Masters degrees aren’t as varied as the Bachelors programs as they have very specific foci. I know several teachers with multiple Bachelors degrees, so it isn’t as odd as it sounds.

Do you think you will settle down and teach in Oklahoma? If so, check out the Oklahoma Department of Education on line for their requirements.

Good Luck! Hope the next four years goes quickly and safely for you!