I completely disagree with you. In some cases, students may mess around in class, or whatever, and they wont learn what they were supposed to. In addition, at my school, we do some long projects, that take 3+ months, including countless hours spent working on it at home. Without the work at home, these would take more like 7 months.
Also, what grade are you referring to? Because all through elementary school I got no homework, and agree with that.