Monday, January 31, 2011

Equivalent Fractions

Almost a half century ago, my teacher taught a math lesson that I still remember today. We were learning how to add and subtract fractions, and she explained how to make equivalent fractions in order to have a common denominator. She started by asking us to multiply 1/2 by 1, 3/4 by 1, 5/6 by 1, etc. Then she wrote several names for 1 on the board - 2/2, 6/6, 10/10, etc. She explained that we could multiply the numerator and denominator by the same number without changing the value of the fraction because we were really multiplying by 1. I realize now that she was teaching us both the how and why in math, and I think that is why I still remember the lesson and have been able to manipulate fractions ever since.

Whenever I help students learn to make equivalent fractions, I always try to replicate my teacher's lesson. This week, I came across a great visual in a Wikiversity article and decided to make a laminated version on 4 x 6 cards, so students could use them with dry erase markers. I think this will help them understand what they are doing and why they are doing it.

February 2011 Last week I started making the cards reversible by changing from multiplication to division, so they can also be used to reduce fractions to lowest terms by dividing by a form of one. Students have had very positive responses to these cards.


  1. I want one of those. Way cool idea!

  2. Rock on!

    I draw this on the board and call it the BIG FAT ONE. I've done it so many times that my BIG FAT ONE looks pretty good and I can do it super-way-fast.

    Here's a pix:!/MathPsych/status/180419316276146176/photo/1

    I love the idea of doing a ton of them, too. I've never done that.

    Thanks, Sue!

  3. Bon - You make a great looking BIG FAT ONE!

  4. This is nice article for equivalent fractions . nice work u are the best article writer . . . . cheers

  5. Thank you for the nice compliment. I was lucky enough to be allowed to learn math in a way that made sense to me. I try very hard to help students learn math in a way that makes sense to them.