here in WA kids don't have to legally go to school (or declare to HS) unitl age 8. I specifically asked the elementary school this summer what they would and could do if my kindergardener missed too much school.... they said "we frown upon missing school for anything other than illnesses. But otherwise, there is nothing we can do". After age 8, I have no idea. If they found out that I was OK with all the unexcused absenses, I assume they might call CPS. But given that I am always willing to HS, I would not let it get to that point.