I did my masters in education and paid for almost none of it myself, with the exception of books and fees. We also had a penalty if we didn't start graduate work -- I think we had five years to move up the pay scale or our pay would be frozen.
In my area, you are given tuition waivers for supervising student teachers. The university the student is from issues the waiver. It's like a coupon for credit hours. I did this as much as I could, whenever I could. I also put the word out that I was in grad school. Often there were colleagues who supervised student teachers who didn't need the waivers. I was pleasantly surprised by how often people would pass along their waivers to me when they weren't using them. I NEVER asked, but accepted anytime one was offered. Then I just planned my grad classes based on how many waivers I had. It was usually 1-2 credit hours for supervising sophomore and junior clinical students. Those are easy, they seemed to mostly be there to observe. Supervising a senior student teacher is WORK, but we were given considerably more credits -- maybe six? I can't remember. You earn them, though.
I also kept my eyes and ears open for scholarship opportunities. In my area, our local legislator offers teachers scholarships for summer graduate work. It was competitive -- I had to write and essay and answer some questions, but it paid for a semesters courses. I took a full load that summer!
I also transferred in as many credits as my program would allow me. In my area, many of the free/low cost teacher training programs you might do to earn CEUs offer optional graduate credit for an additional cost. There was additional work involved as well. Often, that cost was much less than the cost of credit hours at the university I was pursuing my degree. So, I did as many of those as I was allowed to.
It took me a little while to finish, but that was fine. Look into the specific details of your contract -- I only needed 15 hours in addition to my BA to move up the pay scale and avoid the pay freeze. So, you may only need a few classes to fulfill your contractual obligation and then you can finish the rest as you can afford.
Teaching masters programs tend to be different from a "normal" masters in that they are designed for working people who pursue coursework in the evening/summer/weekends. You most likely will not be signing up for a semester's work, but rather taking a course or two at a time until you're finished.
