Point is, whatever it takes to get students actively involved with the reviewing process where they are not bored and effectively reviewing grade level material in order to prepare them for state or quarterly assessments.
When a child learns to relate math to everyday questions, he will be great at it from the simplest addition all the way to trigonometry. To convert percentages, decimals and fractions is thus one essential skill.
However for the most part, when a worksheet is needed to help drill down a procedure, standard, or lesson, its effectiveness can and will vary.
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.