Seven hours is more than enough if you get rid of the following: diveristy classes, self esteem classes, pointless assemblies, the option of 2 studyhalls, a lot of social studies lessons etc. Also don’t make science optional and require math every year along with teaching phonics and real language (not writing poems or asking how a book makes you feel)
“Seven hours is more than enough “
Or if you home school, a good thorough HS education with AP math and serious English and foreign language and etc. can all be had in 4-5 hours a day.
Two of mine entered college at 16, no problem.
They don’t have to go to college at 16 or go at all to prove anything; I just mention it as a possibility. Twelve hours a day is nasty and counterproductive.