I don't ever endorse any specific product or company, but here is a great resource to all my parents wanting to find some summer activity books and software:
Summer is a great time to do FUN academic challenges. The goal isn't to learn Algebra, because your child will learn it in school this Fall. However, summer activities can get his/her brain ready to learn!! So, check out the web site (you can search by grade-level or topic). The products are 100% guaranteed.
As always, I'm here to help! Everyone is good at math, perhaps they just don't...