Curated OER
Factors for Grade 6: HCF, GCD and GCF
In this factors for grade 6: HCF, GCD, and GCF worksheet, 6th graders answer 10 multiple choice questions, about factors and divisors, with answers available online.
University of Regina (Canada)
University of Regina: Math Central: Greatest Common Divisor and Least Common Multiple
Learn about the greatest common divisor, the least common multiple, and the Euclidean Algorithm. This resource gives a description of each of these concepts, accompanied by several examples.
Wolfram Research
Wolfram Math World: Greatest Common Divisors
An advanced investigation of Greatest Common Factors (Divisors) and a look at related algorithms and properties) comutative, associative, and more). Contains links to relevant topics.
Texas Instruments
Texas Instruments: Gcd and Lcm
In this activity students use the Computer Algebra System CAS tool to compute greatest common divisor (GCD) and least common multiple (LCM) of numbers and expressions.
Elias Saab
Math Drills: Lcm and Gcd Quiz
An interactive quiz which provides students with two numbers and asks them to find either the Least Common Multiple or the Greatest Common Divisor between them. Students input their solution and have the program evaluate it. Hints are...
Other
Gcd Training
Use this interactive table to practice finding the greatest common factor of two given numbers. The table can be reset with a new set of numbers for extra practice.
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.
National Council of Teachers of Mathematics
The Math Forum: Learning to Factor
Math Forum Faq which briefly defines greatest common factor and links to an in-depth investigation of how the GCF is found.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Formula for Greatest Common Divisor.
This site is a question and response to a student asking Dr. Math about the greatest common divisor, he gives an interesting way to find the gcd, as well as the button on calculators which commonly does the math for you.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Greatest Common Factors, Least Common Multiples
Math Forum response to request for info on how to find greatest common factors, and how this compares to least common multiples. Explanation includes examples of each.