Even if you don't have immediate plans to return to the US, you might consider doing an online teaching qualification, which could open up opportunities at international schools and/or private schools (Redditors with more experience, am I right on this one?).

More within my experience, I'd say to consider jobs you currently work in from two angles: pay/benefits, and professional development. Especially if you're studying part-time, working in an environment where you can develop as a teacher in the classroom, observe and be observed by experienced teachers, and attend extra training is a massive plus.

A Masters might be a better move if you are interested in university jobs.