Divisibility tests for 2, 3, 4, 5, 6, 9, 10

You can read about divisibility rules here.

Math Antics - Factoring

Prime and Composite Numbers

Factors and Multiples

Prime and Composite Numbers

Math Antics - Prime Factorization

Factoring Numbers (4th Grade)

Prime Numbers and Divisibility Rules

Try out these games:
Number Ninjas (prime factors)
Fruit Splat (prime numbers)

Quiz Yourself

Intro to Factors

Watch this video to get a head start on math lessons that we will get to later this week.

Greatest Common Factor (GCF)

You book has some great online help for GCF.  You can also take a quiz.

Check out the GCF lesson on math.com.
You can also try GCF on mathisfun.com.