Cool Math has free online cool math lessons, cool math games and fun math activities. Really clear math lessons (pre-algebra, algebra, precalculus), cool math games, online graphing calculators, geometry art, fractals, polyhedra, parents and teachers areas too.
Just another supplemental website about Elementary Math. PROS: Free; Includes Basic Math, Advanced Math, and Pre-Algebra; comes with lessons and games. CONS: too "text-y" for students; ads
A Maths Dictionary for Kids is an animated, interactive online math dictionary for students which explains over 600 common mathematical terms and math words
IXL is the Web's most comprehensive K-12 practice site. Widely used by schools and families, IXL provides unlimited practice in more than 4,000 math and English topics. An adaptive learning system features games and awards, inspiring students to achieve.