Wolfram Research
Wolfram Math World: Factorial
This page gives a very complete description of the use of factorials in mathematics. The most general information is at the top.
Oswego City School District
Regents Exam Prep Center: Factorials
This math tutorial defines factorial notation and features practice problems and a teacher resource page.
National Council of Teachers of Mathematics
The Math Forum: Why Does 0! = 1?
Dr. Math describes the reasoning behind 0! = 1.
Shmoop University
Shmoop: Basic Statistics & Probability: Factorials
The probability resource investigates factorials. Students learn about the topic through notes and examples. The tutorial consists of practice exercises to check for comprehension of the concept.
Math Slice
Math Slice: Math Match Game
Test your geometry aptitude using this interactive matching game. Match pictures and symbols to the correct definition. Answers are verified immediately. Winners can earn as much as 10,000 dollars and have their name posted for the day.
Wolfram Research
Wolfram Math World: Topics of Permutation
This MathWorld site is a lite to link to a multitude of sites involving permutations. Look through to find your specific needs. If you are looking at this site with regards to a probability and statisics class you will probably want to...
Math Medics
S.o.s. Math: Algebraic Identities
This online tutorial contains the binomial formula and examples.
Other
Lake Tahoe Com. College: Fundamental Counting Principle
Explains the fundamental principle of counting, which is the beginning point for any study of counting techniques such as combinations and permutations.