Actually, it IS funded and required for public schools in Michigan, to the extent that the current Governor and Legislators now fund the public schools, which isn't very well, thank you. But it's NOT a requirement for Private Schools, Charter Schools, or Internet @ Home Schools. They don't have to provide, won't provide, or can't provide physical education, health, art, music, or band. They don't offer theater, dance, debate team, chorus, book club, glee club, or any other kind of club. No football, baseball, hockey, tennis, swimming, basketball, wrestling, track, cross country, robotics, or cheerleading. And no transportation to and from school or transportation to and from any extra curricular events, field trips, etc. if there were any.
And people really believe that teacher's salaries are the reason charter schools can provide a poor education for their children for less money.