Teachers give their students homework for three basic reasons: to get students to do the required practice on their own, to identify problem areas and because they are required to do so by the school district.
Many subjects, especially mathematics, simply require repetition to instill the habit and right reasoning required to perform the skill. Classroom time would be wasted if every child put in all the math practice time they require to master a skill while in the classroom. There are many other subjects and activities that must be completed each day. By assigning homework, teachers help students learn to apply themselves to their tasks, as well as master skills. In college and in the workforce, individuals must know how to apply themselves to their responsibilities and to accomplish them correctly and in a timely manner. (Just try explaining how the dog ate your tax return).
When students work on homework, they may or may not have access to assistance. In either case, teachers use homework assignments to evaluate how thoroughly a students has learned the material and if they may need a different approach or more rudimentary training in that area before moving forward. Teachers can also use homework to share with the rest of the student's family what is being covered in school. Homework gives students the opportunity to test themselves on skills before they are tested in the classroom. A poor grade on homework alerts everyone, teachers, students and family that the student is struggling with something before it can ruin their course grade.
Too many school districts require so many hours of homework each day in each subject, whether the student needs it or not. This is wasteful and counterproductive. Students who are succeeding in feel resentful, teachers become overworked with grading papers unnecessarily and students who are struggling feel even more overwhelmed and are more likely to drop out. The arbitrary assignment of homework by school districts, simply as a matter of policy, should be banned. Teachers receive intensive training on learning and teaching methods, working with students to help them succeed and in developing worthwhile lesson plans. Artificial homework guidelines have nothing to do with the individual nature of teaching or learning.
Homework is a useful tool for practicing skills and for identifying problem areas. Teachers use homework for a variety of valid reasons, all of them related to the education and problem-solving skills of their students. Parents are right to protect excessive use of homework. In light of current childhood weight issues, children need time to be children, to run and climb and play like children. They should not be treated like office workers, bound to a desk for eight or more hours each day.