Accentuate the Negative

Introduction to the Coordinate Plane

Math.com: The Coordinate Grid

Math League: Lessons On Integers

Triple A Math: 7th Grade Topics (look for + and - integers)

Math Guide: Practicing Integers

Math.com does Signed Numbers

Math.com does Adding  & Subtracting

Math.com does Multiplication & Division

 Integers Menu: Math Wizz

Amby's Math Resources: Operations with Integers

Just the Facts: Fact Monster

Ask Dr. Math: Math Forum (Integers, Rational, & Irrational Numbers)  

Funbrain Presents: One False Move

Purplemath Does Integers

More Funbrain: Add & Subtract

Add & Subtract with 2-Color Counters

Funbrain Again: All Operations

Line Jumper (Select "Hard" to "Super Brain" level)

What Is It? Defining Rational Numbers

Defining Rational & Irrational Numbers (Regents Prep)