Steer him towards the hard subjects, like science, mathematics, or engineering (aka STEM). Because these subjects require rational and logical thought, the kids taking them are less likely to fall for the leftist brainwashing. This is true even in a liberal school--I went to UC Davis, which is second only to UC Berkeley in lunatic leftism, but was largely insulated against the wacky liberal garbage.
Also, start him off with community college. The education there is just as good, it is less expensive, and since many of the students are working adults, the leftism is less rampant there.
yes. perhaps he can graduate at tenth grade and head straight for community college. He is very strong in math they do Saxon Math. He is really enjoying Latin and loves the literature/history where the teacher sets up regular debate scenarios on such as Crusades (pro-vs, con) and other political matters from the history. They must memorize key historical events from Egyptians settling along the Nile River Valley all the way to 9-11. Each event has some time of motion or posture to go with it. They are big on memory work-he must recite long poems.Right now they are reading Beowolf-the full version.