Homeschool Math has worksheets available for 6th grade math concepts as well as numerous middle school math concepts applicable to many grades http://www.homeschoolmath.net/worksheets

Khan Academy has videos on concepts such as Arithmetic and Pre-Algebra, Algebra, Geometry, Probability, Statistics, and Brain Teasers. There is also practice available with the videos. http://khanacademy.org

Math is fun provides games, puzzles, lessons, and online activities in such topics as algebra, geometry, measurement, and data http://www.mathisfun.com

Patterns, Functions, and Algebra

This website will allow you to create free algebra worksheets.

http://www.math.com/students/worksheet/algebra_sp.htm

General Math Websites

Kuta Software will allow you to create free algebra worksheets.

http://www.kutasoftware.com/free.html

Homeschool Math has worksheets available for 6th grade math concepts as well as numerous middle school math concepts applicable to many grades

http://www.homeschoolmath.net/worksheets

Khan Academy has videos on concepts such as Arithmetic and Pre-Algebra, Algebra, Geometry, Probability, Statistics, and Brain Teasers. There is also practice available with the videos.

http://khanacademy.org

The following iXL websites provide practice questions specific to each grade

http://www.ixl.com/math/grade-6

http://www.ixl.com/math/grade-7

http://www.ixl.com/math/grade-8

http://www.ixl.com/math/algebra-1

AAA Math websites provide information and examples including practice problems to grade specific concepts

http://www.aaaknow.com/grade6.htm

http://www.aaaknow.com/grade7.htm

http://www.aaaknow.com/grade8.htm

Brightstorm provides videos on Algebra and Geometry concepts

http://www.brightstorm.com/math/algebra/

http://www.brightstorm.com/math/geometry

Brain Pop contains videos, practice, and activities based on many different math concepts

http://www.brainpop.com/math

Math Goodies features lessons and worksheets for middle school students

http://www.mathgoodies.com/

Math is fun provides games, puzzles, lessons, and online activities in such topics as algebra, geometry, measurement, and data

http://www.mathisfun.com

Other:

http://www.mathplayground.com

http://www.brainfun.com

http://www.crctlessons.com

http://math-play.com

http://www.sheppadsoftware.com

http://usmint.gov - go to the education tab, under kids games

http://www.quia.com

http://nlvm.usu.edu - National Library of Virtual Manipulatives