Harcourt Multimedia Math Glossary
http://www.harcourtschool.com/glossary/math2/index_temp.html
A glossary that includes definitions and examples for common and uncommon math words. Click on your grade level to begin.

Activities for Your Day
http://www.illuminations.nctm.org/swr/review.asp?SWR=1919#
This site, sponsored by the US Department of Education, recommends many math activities that parents can utilize no matter how busy their days are.

Attribute Trains
http://nlvm.usu.edu/en/nav/frames_asid_271_g_2_t_3.html?open=instructions
Practice completing patterns of shapes, numbers, or colors.

Line Jumper
http://www.illuminations.nctm.org/swr/review.asp?SWR=2177#
This activity, framed as a simple online game, gives students practice in solving addition and subtraction problems using a number line.

Circulating Coins
http://www.usmint.gov/kids/index.cfm?fileContents=coinNews/circulatingCoins
Everything you wanted to know and more about the penny, nickel, dime, quarter, half-dollar, and one-dollar coin.

Spinners
http://nlvm.usu.edu/en/nav/frames_asid_186_g_1_t_1.html?open=activities
Work with spinners to learn about numbers and probabilities.

Adjustable Spinners
http://Illuminations.nctm.org/tools/tool_detail.aspx?id=79
This tool allows students to create their own spinners and examine the outcomes given a specified number of spins. Students learn that experimental probabilities differ according to the characteristics of the model; they also grapple with the idea of variability–that two identical spinners or dice may not produce identical experimental data.