Other
Help With Fractions: Prime Numbers Chart
Prime and composite numbers are defined on this website. A prime number chart is also included for all prime numbers under 10,000.
University of Waterloo (Canada)
Wired Math: Primes and Prime Factors [Pdf]
Explore primes, prime factors, and composites using this collection of worksheets. Lots of detailed examples, interesting math facts, and colorful visuals. Acrobat Reader required.
University of Cambridge
University of Cambridge: Nrich: Two Primes Make One Square
On this one page website sharpen your logic, prime numbers and square numbers skills while working on this challenge. The solution is available to double check your solution.
University of Cambridge
University of Cambridge: Nrich: A Conversation Piece
On this one page website sharpen your logic, division and prime number recognition skills while working on this challenge. The solution is available to double check your solution.