In this blog/video I want to take you a little bit deeper into the world of … the LCM! Yes, that fascinating little mathematical entity is beckoning us to explore it further. Several readers wrote to me after I posted my LCM “trick,” saying they want to see me demonstrate WHY this “shortcut” works. One [...]

# Archive | Elementary Math

The category for all things about Elementary Math.

# Problem of the Month – January 2013

Twelve is the first number with two pairs of factors (2 x 6 and 3 x 4). Primes, on the other hand, have no pairs of factors other than the trivial pair of one and the prime number itself. Considering that contrast, here’s an interesting fact about primes and the number 12. Add 12 to [...]

# The “Ladder of Primes”

Prime numbers help us reduce fractions Using the “Ladder of Primes,” students can more easily and more quickly reduce fractions to lowest terms.

# Quick Easy Way to Untangle Confusion re: “Greater” and “Less”

Once students learn about negative numbers and absolute value, the concept of greater and less becomes a bit “cloudy.” What was once clear is now “muddied.” But there is an easy way for students to tell which of two numbers is greater and which is less. That method involves looking at the numbers on the number line and using a memory trick derived from the spelling of the words “greater” and “less.” Enjoy!

# Secrets of the Calculator, Part 1

Calculators can be great assistants when doing math. Unfortunately many students are unaware of the capability of many calculator keys. This is the first in an occasional series of posts that will help students learn how to make better use of the calculator.

# How to Decrease Mistakes in Algebra – Part 3

The double-slash helps students for a variety of reasons. This post explains some of the reasons why it works.

# “Math Cafe” Gives Students Options for Math Success

Students like to order off of menus when they are in math class. That means that they like to learn a variety of approaches and then choose the method that works best for them. This post shows teachers how they can teach the same skill in a variety of ways and thereby give students more ways to successfully work the math problems.

# New Approaches to Help Students Overcome Math Struggles

The teaching technique of finding out and helping students learn the “baby steps” that make up the larger math processes is having success through an organization called “Jump Math.” Read about it on this post.

# How to tell if a Number is Divisible by 8

How to tell if 8 divides into a number. There is a simple test for this. This post explains this.

# How to See Why the Divisibility Trick for 3 Works

There’s a nifty trick for finding out if 3 divides evenly into a number. This little proof shows why the trick works.