The last time I checked, there were still only 24 hours in a high school student’s day. Into this amount of time must be crammed school, homework, piano lessons, talking on the phone, tennis practice, a volunteer job and a bare minimum of sleep. Some would insist that homework should get first priority, and that extra-curricular activities and everything else should fill any gaps in the day. Those people are dead wrong.

The number one problem with increasing the amount of homework is simple—there is absolutely no proof that it works. Over the years, homework has been subjected to a series of controlled trials. The conclusions showed extraordinary variability. Even in regard to specific areas of application such as within different subjects, grades or student ability levels, the reviews directly contradict one another.

If a positive correlation is established, it is not clear whether homework makes motivated students or if it is the privileged and motivated students that do their homework. Many countries with the highest scoring students, such as Japan and Denmark, have teachers who give little homework. At the other end of the spectrum, countries with very low average scores—Thailand, Greece and Iran—have teachers who assign a great deal of homework.

Over the last decade and half, children as young as nine to 11 have seen a nearly 40 percent increase in homework. Duke University’s Harris Cooper concluded that homework does not measurably improve academic achievement for young students. That’s right—all the sweat and tears do not make Johnny a better reader or mathematician.

Homework also comes with many negative side effects. Ethnographic research shows that extensive homework has played a major role in school dropouts. In interviews with high school dropouts as part of a study for the Maine Department of Education, students were asked if there was a moment when they knew they were going to drop out. They vividly described situations with incomplete homework and parent-child conflict exacerbated by homework demands that “seemed to grow as fast as the time parents have available shrinks.”

Most teachers are not making efficient use of homework. While drills and exercises have their place in schooling, homework is clearly not that place. But that doesn’t even include the amount of time it cuts off from other activities, like free time. Free time plays a key role in fostering both creativity and emotional development, factors just as basic to long term success as an academic gains.

A modest amount of independent work, around two hours a day, is more appropriate for high school students. Instead, teachers or other adults with appropriate skills should also be paid to assist students in more independent projects that would advance their learning.

Punishing students with work is clearly not the way to go. If schools can’t mend their ways and reduce their students’ homework, then the only option is to let a no-homework policy to become the default. Students shouldn’t be forced to labor more than 40 hours a week. After all, that’s the standard the adults set for themselves.