National Council of Teachers of Mathematics
Nctm: Figure This: How Much Time Do Teens Spend on the Job?
Try this math challenge where you investigate the average number of hours teen actually spend working. Apply your problem solving, number sense, and computation skills in this one page activity from the NCTM Math Challenges for Families...
BBC
Bbc: Standard Deviation
A demonstration of how to find the standard deviation of a set of data. Several examples and a practice test are offered.
Free Math Help
Free Math Help: Batting Average
Here is an explanation about how to calculate a player's batting average.
Mocomi & Anibrain Digital Technologies
Mocomi: What Is Average?
Defines how to calculate average and gives examples.
AAA Math
Aaa Math: Statistical Mean
Learn about finding the statistical mean of a set of data, and then do some practice problems.