A poll conducted for the Associated Press earlier this year found that about 57 percent of parents felt their child was assigned about the right amount of homework. Another 23 percent thought it was too little, 19 percent thought it was too much.
Educators should be thrilled by these numbers. Pleasing a majority of parents regarding homework and having equal numbers of dissenters shouting "too much!" and "too little!" is about as good as they can hope for.
But opinions cannot tell us whether homework works; only research can, which is why my colleagues and I have conducted a combined analysis of dozens of homework studies to examine whether homework is beneficial and what amount of homework is appropriate for our children.
The homework question is best answered by comparing students who are assigned homework with students assigned no homework but who are similar in other ways. The results of such studies suggest that homework can improve students' scores on the class tests that come at the end of a topic. Students assigned homework in 2nd grade did better on math, 3rd and 4th graders did better on English skills and vocabulary, 5th graders on social studies, 9th through 12th graders on American history, and 12th graders on Shakespeare.
Less authoritative are 12 studies that link the amount of homework to achievement, but control for lots of other factors that might influence this connection. These types of studies, often based on national samples of students, also find a positive link between time on homework and achievement.
Yet other studies simply correlate homework and achievement with no attempt to control for student differences. In 35 such studies, about 77 percent find the link between homework and achievement is positive. Most interesting, though, is these results suggest little or no relationship between homework and achievement for elementary school students.
Why might that be? Younger children have less developed study habits and are less able to tune out distractions at home. Studies also suggest that young students who are struggling in school take more time to complete homework assignments simply because these assignments are more difficult for them.
So, how much homework should students do? The National PTA and the NEA have a parent guide called "Helping Your Child Get the Most Out of Homework." It states, "Most educators agree that for children in grades K-2, homework is more effective when it does not exceed 10-20 minutes each day; older children, in grades 3-6, can handle 30-60 minutes a day; in junior and senior high, the amount of homework will vary by subject…." Many school district policies state that high school students should expect about 30 minutes of homework for each academic course they take, a bit more for honors or advanced placement courses.
These recommendations are consistent with the conclusions reached by our analysis. Practice assignments do improve scores on class tests at all grade levels. A little amount of homework may help elementary school students build study habits. Homework for junior high students appears to reach the point of diminishing returns after about 90 minutes a night. For high school students, the positive line continues to climb until between 90 minutes and 2½ hours of homework a night, after which returns diminish.
Beyond achievement, proponents of homework argue that it can have many other beneficial effects. They claim it can help students develop good study habits so they are ready to grow as their cognitive capacities mature. It can help students recognize that learning can occur at home as well as at school. Homework can foster independent learning and responsible character traits. And it can give parents an opportunity to see what's going on at school and let them express positive attitudes toward achievement.
Opponents of homework counter that it can also have negative effects. They argue it can lead to boredom with schoolwork, since all activities remain interesting only for so long. Homework can deny students access to leisure activities that also teach important life skills. Parents can get too involved in homework -- pressuring their child and confusing him by using different instructional techniques than the teacher.
My feeling is that homework policies should prescribe amounts of homework consistent with the research evidence, but which also give individual schools and teachers some flexibility to take into account the unique needs and circumstances of their students and families. In general, teachers should avoid either extreme.