Students reported bringing home an average of just over three hours of homework nightly (, 2013)."I think there's a focus on assigning homework because [teachers] think it has these positive outcomes for study skills and habits.But we don't know for sure that's the case." Even when homework is helpful, there can be too much of a good thing.Now, as schools are shifting to the new (and hotly debated) Common Core curriculum standards, educators, administrators and researchers are turning a fresh eye toward the question of homework's value.But when it comes to deciphering the research literature on the subject, homework is anything but an open book. Spend more time practicing multiplication or studying Spanish vocabulary and you should get better at math or Spanish. Homework can indeed produce academic benefits, such as increased understanding and retention of the material, says Duke University social psychologist Harris Cooper, Ph D, one of the nation's leading homework researchers. In a review of studies published from 1987 to 2003, Cooper and his colleagues found that homework was linked to better test scores in high school and, to a lesser degree, in middle school.Yet other evidence suggests that some kids might be taking home much more work than they can handle.Robert Pressman, Ph D, and colleagues recently investigated the 10-minute rule among more than 1,100 students, and found that elementary-school kids were receiving up to three times as much homework as recommended.Both the National Education Association and National Parent Teacher Association support that limit.Beyond that point, kids don't absorb much useful information, Cooper says.There's often intense pressure to succeed academically, from both parents and peers.On top of that, kids in these communities are often overloaded with extracurricular activities, including sports and clubs. "Some kids have up to 40 hours a week — a full-time job's worth — of extracurricular activities." And homework is yet one more commitment on top of all the others.