Shmoop, a publisher of digital educational resources, has added pre-algebra to its list of free learning guides. The online Pre-Algebra Learning guides contain hundreds of topics with succinct explanations, diagrams, interactive examples, practice problems, and real-world applications. Pre algebra is Shmoop's first foray beyond its core humanities offerings. At the home page click on the pre algebra tab
XP Math is a good place to find math games, math videos, math worksheets, and math e-books. The games section of XP Math offers games for basic arithmetic, algebra, geometry, and probability. Create an account on XP Math and you can keep track of your scores.
There is a free trial version of the materials in the National Library of virtual manipulatives. Math topics Numbers and Operations, Algebra, Geometry, Measurement and Data Analysis & Probablity are covered. I did not come across anything asking for money so I a not certain there is a cost. There are tons of manipulatives to access from each of the above categories. This site is associated with the Uta State University.
Looks like an interesting site. Please share with anyone you feel may be interested. This is also another site to share with parents via your teacher web page.