Are the problems too close together? Make sure you can distinguish between the problem number and the actual problems. The problem numbers should be less obtrusive. Students with and without ADD and ADHD can become distracted by too many distractions!?
For seven years I've watched my beautiful son hunched over Kumon math worksheets. He finds little enjoyment from them and I'd rather see him chasing butterflies. They've certainly helped his Math performance at school __ he's top of his class, but I wonder if the effort has been worth it in the big scheme of things. He's currently solving about 100 polynomials per day. Man, he can really solve polynomials, and fast. But for what?