Fraction Number Strings

We are knee deep into our fractions unit and I wanted to share something that has been rather successful in getting my students to recognize landmark fractions and decimals:  Number Strings.

What are number strings, you ask?  Well, they are similar to number talks in that it is a way to get the kids to *mentally* think about the math that they are doing.  What makes them different is that the number strings focus on ONE strategy to get the students solving problems, as opposed to the several strategies that number talks promote.

Since we are working on adding and subtracting fractions, my math coach gave me this book Minilessons for Operations with Fractions, Decimals, and Percents: A Yearlong Resource (Contexts for Learning Mathematics) to help me get started.  The first number string that is presented shows the kids how to equate certain fractions with money.  Money is so common amongst the kids, that they instantly related.  Showing the kids that 1/2 is just like $0.50, or two quarters....well, they get it.  Then you tell them that 1/4 is like $0.25 or 1 quarter.  Bingo...lightbulbs.  So if you add 1/2 + 1/4 it is like adding $0.50 and $0.25.  That is $0.75, or three quarters....3/4!  Boom!

Once you show them that, you do another problem, this time with 3/4 + 1/2. Since they already know those landmark decimals, it isn't too hard.  $0.75 + $0.50 = 5 quarters or $1.25 or 1 1/4.

This was our first number string.

I promise you, ALL of this was done in their head.  All of it.  I just wrote down what they said.

The next day, we added 1/5 in there.  1/5 = $0.20.  And 1/10, which was $0.10.   And 1/20.  When I asked my students what they thought 1/20 was, there was literally no hesitation.  Hands went up all around saying $0.05.

Then, we did mixed numbers and improper fractions.

Then subtraction.

Seriously, these are amazing.  The kids are adding fractions with unlike denominators IN THEIR HEADS!!  I can not believe it.  There has been a shift in the way that they even think about fractions.  Equating them to decimals naturally really has made all of the difference in the world.

Now this is only the first strategy that the number strings book presents. There are MANY, MANY more.  They truly are fantastic.  If you already do number talks, this is a must to add.

A great website to check out is Number Strings.  There are so many great ideas there too!

Do you do number strings?  Do you have any advice you care to share?