Cool Math
Coolmath: Coolmath4kids: Addition
A set of seven short tutorials on addition. Begins with a basic introduction to how addition works, and covers topics such as using a number line, place value, and regrouping.
PBS
Pbs Learning Media: Cooking Contest
In this Cyberchase video segment, Matt uses subtraction to help Digit figure out how much time he has left in a cooking contest with Hacker.