I got a masters in English while teaching, but I didn't have any kids at the time. Something always has to give somewhere. I'm definitely not trying to criticize you as the demands on teachers are way more than they should be.
When I got my Masters, I was only a teacher's aid/para-professional. I took no work home. Yes, you are so right. They always pile more and more on the teachers. It's hard being married with 2 kids.