Does homework improve academic achievement? Yes, according to a recent Duke University study, but too much homework can be counter-productive.

Researchers at Duke University in Durham, North Carolina have reviewed more than 60 studies on homework between 1987 and 2003, and concluded that homework does have a positive effect on student achievement.

Harris Cooper, a professor of psychology and director of Duke's Program in Education, said the review that he led showed this positive link with homework was much stronger for secondary students (grades 7 through 12) than those in elementary school. While it's clear that homework is a critical part of the learning process, the research also showed that too much homework can be counter-productive for students of any grade level.

Professor Cooper noted that the study was consistent with the "10 minute rule", a commonly accepted practise in which teachers add 10 minutes of homework for each grade a student completes. A grade 4 student, for example, would be expected to complete 40 minutes of homework a night, while a senior-level high school student would be expected to do about 2 hours. More than 2 hours of homework per evening did not result in higher achievement for the student.

The study suggests a number of reasons why older students benefit more from homework than younger students:

  • younger children are less able than older children to tune out distractions in their environment, and have yet to develop effective study habits.
  • teachers perhaps use homework to help younger students develop better time management and study skills, not to improve their achievement in specific subjects.

To avoid homework "burn out", the amount and type of home studies should vary according the individual child's developmental level and home circumstances. The bottom line for the authors of the study is that kids should be doing homework. For young students, the assignments should be short, able to be completed without much struggle, occasionally involve parents and, when possible, use after-school activities that kids enjoy, such as sports or high-interest reading.

Professor Cooper points out that there are limitations to current research on homework. For instance, little research has been done to assess whether a student's race, socioeconomic status or ability level affects the importance of homework in his or her achievement.

This is Prof. Cooper's second synthesis of homework research. His first was published in 1989 and covered nearly 120 studies in the 20 years before 1987. His recent paper reconfirms many of the findings from the earlier study. Prof. Cooper is the author of "The Battle over Homework: Common Ground for Administrators, Teachers, and Parents" (Corwin Press, 2001)

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