Bloody hell, these replies, you're probably getting put through the wringer because you've got 3 kids. Have people missed that you have a 2yo?
My DH WFH, flexible hours but lots of them and does a full time job, some consulting hours and a business on the back burner when he can. Also makes dinner every night and does bulk of the big cleaning. I have our toddler nearly all the time apart from my 3 working days but do all drop offs, pick ups, meals, bath time bedtime etc and he comes in with me for the last bit of the night still - weaning off breastfeeding. He says he's happy with it and it's how he feels useful given that he couldn't share feeds at night and keeps quite nocturnal hours. He's also very particular about things like how to clean the stove or bath etc so he's quite happy doing them.
Homeschooling - great if you can cope but sounds like you're finding it tough and as a fellow teacher, I do wonder how you're managing year 7 work with juggling two toddlers.
I do think it sounds like your DH has a fair amount of leisure time in the evening and it's not fair that you have none - and if you put your kids in school then you'd still have no break looking after the 2yo all day. And if you went back to teaching, yes you'd have holidays but then your older kids would be home with you too. I don't think anyone needs several hours of chilled time to themselves every night while their wife struggles, and this isn't just about you homeschooling.
Your DH does sound kind of resentful so may be a discussion if he wants some pressure taken off and you bringing in some part time income - okay then but that's got to allow for some breaks for you as well. Or you could make the decision yourself to go back to work or run some tutoring classes since you're qualified. Sounds like he was on board with the homeschooling but could have changed his mind?
Also sorry if he hates his job, he needs to be a grown up and have an adult discussion with you especially if he refuses to consider looking elsewhere. I've absolutely hated jobs before and had to stay in them for financial reasons. Doesn't mean I'd have been fine with my husband getting zero downtime while I decompressed every evening - he could give you an hour or two a week with no threat to his mental health.