In a 2017 meta-analysis of 11 studies, researchers concluded that “homework assignments had a small effect size on students’ academic achievement levels.” But analyzed by grade level, a different picture emerges: While the benefits are trivial for elementary students, they rise dramatically for middle and high school students.

The homework debate provokes passionate feelings on both sides of the ledger. Many teachers insist on giving none, citing the small effect sizes and intrusion into family, work, and play time. Others say that homework helps students develop good study habits, reinforces material covered in class, or supports activities—such as reading novels or working on independent projects—that don’t fit neatly into the school day.

There’s room for both arguments.

In the early grades, beyond establishing a daily reading habit, there’s simply not much to commend regular take-home work. The National Education Association supports a nightly maximum of 10 minutes of homework per grade level—but many teachers point out that arbitrary time commitments promote busywork, when what really matters is the homework’s quality and relevance.

As always, moderation and common sense are key: Assign homework sparingly, consider low-stakes approaches like allowing students to opt out of some assignments, or count homework as extra credit. Finally, when in doubt, follow Principal Peter Badalament’s lead: Ask kids how much time they’re spending on homework, and then make adjustments.