Students explore fractions under and over one whole using a number line in this activity.

This WebMath site shows how to add, subtract, multiply and divide through a step by step examples. The user simple selects the operation and types in two numbers, and the computer solves the problem through a step by step process. Also...

You can pick up some valuable ratio pointers here. When you finish working your way through the three instructional pages, go on to the Activity for some practice, or take an online "Test Bite" and check your understanding.