Homework is helpful, but only in some cases. Generally there are two types of work assigned - problem sets and "busy work". In courses like mathematics, physics or computer science, one gets assigned problem sets which are focused on the reinforcement of the new material. Since such courses are focused on the understanding and application of the material - extra practice is helpful in fulfilling the desire educational goal.
On the other hand, the courses such as English or History do not require homework to reinforce the concepts. These courses are notorious for the "busy work" students are assigned whenever they are a part of such course.In this case homework is harmful and it only wastes the time of the students.
Homework, when used well, can be a great tool for learning, and should be used as a small part of a teacher's arsenal. If used in the right way, the good can outweigh the bad for most students.
Homework encourages students to interact with the material before the test, but with no pressure, to show them if they really understand the material. If they don't, they can always ask the teacher later. This reduces the temptation to "cram," as well, so as to avoid the social stigma of being someone who skips out on homework.
Additionally, homework can be a powerful diagnostic aid to teachers, who can use it to judge the effectiveness of their lessons.
We also need to bear in mind that all students are different, and learn better through differing methods. It is the teacher's unique challenge to provide a lesson plan that provides the greatest benefit to all of his/her students. Some students learn better through hands-on activities, some through reading, some through hearing it explained, still others from doing it by themselves, and putting the pieces together by themselves. Homework can be a great benefit for students in the latter category.
homework is obviously helpful. Firstly it enables teachers to know which students are ready to move onto the next topic and which aren't as in a busy classroom its hard for a teacher to know who's copying who. Secondly it lets students prepare for adult life by teaching them disipline. Thirdly it teaches children to do well in exams and even if the student can do the work it never hurts to practise. There was one comment that said "in english and history students don't need to do any homework", in GCSE exams you have to write at least 2 essays in the english language exam and at least 3 in the literature exam, how will children be able to do this if they have never done it before??? Homework aides spelling and expands vocabulary. Next, for history revision is obviously needed for exams and this entails some form of "homework". To some students it might be boring, for some tedious but you cannot get past the fact that it benefits their schoolwork and exam results.
Practise is a half of the success. Doing homework might be harmful, since you do not understand some material,however, it is the best way to improve your knowledge. While doing homework, students understand not only one particular material, but also other that they learnt before.To give all power to understand the material will be encourage in the nearest future, when test results will be available.
Homework is helpful because if you won't give homework then whatever is learnt will be not in my mind and there will be no revision of what you have done so it is helpful.