Up until like 6th grade, homework should be manditory. After that though, I think kids are old enough to know "hey, i have to study this to do well". I got b's + on almost every test I took (with the exception of english and spanish), but my overall grades were c's and d's because i saw homework as pointless busywork. It pissed me off to do it so I just did it hap hazardly.
I knew the subject, I saw that reading the same shit that I already knew would serve no point.
Btw, moved to gen con, I don't think the teachers are conspiring against us..