What type of work sheets are you looking for? Reading, Mathmatics or another subject?
I will be happy to try and locate the grade level work sheets for you.
There are several sites online that you can print work sheets, but there are also interactive sites to help with the Pre Algebra problems. This link will take you to a site where you can print out some work sheets:
This is a link for actual online practice that keeps score of correct and incorrect answers: http://www.math.com/homeworkhelp/PreAlgebra.html
These sites are all free. My son had some problems with Algebra and Geometry and I found the interactive site very helpful in him learning and being able to interact as well as having practice work sheets.
Please let me know if you need more sites and I will be happy to add them to the ones posted here. Joan