Virtual Manipulatives : Factor Tree

This game was under the Algebra 6-8. The idea of the game is to find the prime factorization of the numbers given by the computer. You could even enter your own number in order to find the prime factorization of it. Lets say you enter the number 500. It will ask you to input at least one of the factors, any factors. Once you put in 4, it will fill in the other factor, 125. It will then ask you to factor both numbers by inputing one of their factors until only prime numbers are left. Once this is accomplished at the bottom it will tell you the prime factorization of the number. If you enter the wrong factor for the number then it will tell you that 7 does not evenly divide 500. It would be a good reinforment for my class espcially since just recently they learned about radicals. I would be a great way to learn about GCF(Greatest Common Factor), since you can factor two numbers at the same time using the factor tree program.