There are many math_based games available in educational toy stores that will help to reinforce the principles your child learns in worksheets. Computer games can help too, but depending on the age of your child, it is best not to encourage too much computer use at an early age. Everyday activities can be turned into math lessons too. A trip to the grocery store can turn into a math lesson if you encourage your child to help you count how many items you are buying, or add up the bottles of milk as you add them to your cart.
A lot of the websites charge high dollar amount for these math worksheets. Considering your willingness to spend the high dollar, you run in to a new problem _ the uniqueness of the material, a lot of websites offer sheets packed with identical problems leading the child to almost rote memorization of the problems and solution. This leads to deprivation of student and his/her ability to solve the problems logically. And some websites offer sheets in portable document format. And to open such sheets you are forced to download special software.