Are Elementary School Students Assigned Too Much Homework?

WASHINGTON, D.C. (CBS) -- How much homework is too much?

Researchers say first graders today have three times the amount of homework recommended by experts.

According to the study, "In the last 20 years, homework has increased only in the lower grade levels, and this increase is associated with neutral (and sometimes negative) effects on student achievement."

Experts say a good rule is ten minutes of homework for each grade level; ten minutes for first grade, twenty for second grade, etc.

Researchers says high school students may sometimes do more homework, depending on their classes.