AAA Math
Aaa Math: Least Common Multiple
This tutorial offers an explanation of least common multiples, practice finding them and a game to play. There is a lot of information available at this location.
Mathigon
Mathigon: Math Foundations: Divisibility and Primes: Divisibility Rules
There are a few different rules that can make it easy to check if a number is divisible by another. In this lesson you will learn some of them such as,any number that ends in 0, 2, 4, 6, or 8 is divisible by 2, divisibility by 5 we...
Math Aids
Math Aids: Factors Worksheets
Great resource for learning and practicing fractions and their different operations. Math worksheets are printable, may be customized, and include answer keys.
University of Vienna (Austria)
University of Vienna: Elementary Properties of Numbers
Quick interactive assessment which determines skill level on fraction equivalence, prime factorization, and common divisors/multiples.
Varsity Tutors
Varsity Tutors: Hotmath: Graphing Calculator Practice Problems Number Theory
Practice using your graphing calculator for number theory problems, including prime factorization, greatest common factor, least common multiple, and scientific notation. If you get stumped or if you would like to check your work, then...
Alabama Learning Exchange
Alex: My Favorite Number
The activity allows students to review many of the number theory concepts. Students will pick a composite number write verbal expressions about the number, find the factors, prime factorization, list multiples, draw a cartoon character...
Math Aids
Math Aids: Fractions Worksheets
Great resource for learning and practicing fractions and their different operations. Math worksheets are printable, may be customized, and include answer keys.
Khan Academy
Khan Academy: Identify Composite Numbers
Identify composite numbers less than 100. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Other
Stat Soft: Statistics Glossary
Dozens of statistical terms are defined and illustrated in this glossary.