Looking at the new job in isolation from your current burn-out it looks great: a mission you believe in, a team that believes in you, the chance to learn new skills (you are a teacher, you know how that's done) and more pay.
I don't think you need to worry too much about the financial stuff: I've always seen financials as pretty basic: you get the numbers, you work out what they mean has happened, you work out what's going to happen if you don't change anything, you work out what's going to happen if you do change things. Frankly, a lot simpler than dealing with people and a heck of a lot easier than dealing with kids.
I think the bigger issue is how you recover from your current burn-out. When do you need to start the new job and how much time can you take off work before then? If you can do a short resignation period or take sick leave (this is a real thing, not malingering, when a job leaves you burnt out) then you may find that you have time to recover and re-energise for the new job. Lots of sleep, some daily exercise, good food, friends/family and maybe a therapist to unburden yourself to and be validated as how justified your current burn-out is would be my prescription for recovery (and yes, I've been there, done that).