Worksheets also, when used properly, provide both the students and parent / tutor immediate feedback as to the child's progress. This means they can be used to point out areas where the student needs further reinforcement.
Parents, too, can start to see math as the enemy. Teachers may even tell parents that their child "struggles with concepts," a nice way of saying "your kid doesn't get it." But is this the case? Does a middle-school child struggling with math simply not understand the concepts? Often the answer to this question is a resounding "no!"
These students have weak immediacy. This means that compared to other students, they are slow to come up with the right answers to basic math problems like 6 x 8, or 35 divided by 7. While other kids have the answer stored in their memory, these kids do not. This causes big problems when they try to work through the more complex problems they encounter in junior high math.
It is amazing the difference in effort you will get from worksheet to worksheet. Granted the amount of effort may vary immensely from year to year depending on the group of students you have.