The trick is going to be seeing how we can (a) do this in Massachusetts and (
manage things in such a way that I get to keep my job.
If you rent, I would suggest forwarding your address to a maildrop, and moving across town. Use the mail drop as your "real" address.
Then just have him quietly drop out of school. DO NOT ASK PERMISSION or attempt to be a compliant homeschooler. Do not give any government agency, DMV, or voting precint your real address. Ever. Your mail drop is your address.
When he is old enough for college, find a friendlier jurisdiction, and get him a GED.