## Thursday, July 26, 2012

### CRA for Composing and Decomposing Numbers

Okay, I'm having trouble finding different ways to say "composing and decomposing numbers" in my post titles!  But seriously, it's just THAT important, so I keep writing about it.  Our Kinders and Firsties should be doing these types of activities extensively, so it's important to find lots of different ways to approach the skill.  Today I present Clothespin Count.  Students use strips that have dots showing 5 (pictured below) through 10.  Choose the number that your kiddos need to work on.  They don't all need to be working on 5; that's how you differentiate this activity.  You'll need two different colors of clothespins, and you need as many of each color as there are dots on the card.  So, if kids are working on 5, they need 5 of one color and 5 of the other.  Students use a random number generator (several options shown below) and put that many of one color of clothespin on their strip.  Then they complete the number with the other color of clothespin.  Place a Math Talk card in the workstation that says, "____ and ____ make ____" so they use the correct mathematical language to describe the combination they have made.  So in the first picture shown, the student would say "1 and 4 make 5."  They draw another card (or roll the number cube again) and make another combination.

 Using a number card for the random number generator adds an abstract (symbolic) component to the activity.  Now you have concrete (clothespins), representational (the dots), and abstract (the numeral).

 Use a number cubes with dots for the random number generator and kiddos also get to practice subitizing.  Of course you can only use the number cube when working on combinations of 6 through 10.  And if you use it for 7-10, they won't be able to get all the combinations.  Make sense?

 Another option for the random number generator--a card with ten frames or actual ten frames.

 This shows how students can show their work on the B & W version.  As they progress, they could write the actual number sentence instead of using "and" and "make".

 Copy and cut apart strips for workstations.  Strips included for 5 through 10.

Like the number cards shown in the pictures?  Grab them here.

1. Super easy idea and great practice! Love it! Thanks for the great ideas! I can never have enough activities for composing and decomposing numbers!

1. I know, right? Glad you like it. :)

2. Another fabulous idea to add variety for composing and decomposing numbers! Thank you once again!

1. You're welcome, Corinna! I'll TRY to keep coming up with more.

3. Love this idea. Did you paint your clothes pins or were you able to find them in primary colors somewhere?

1. I found them! They are small, plastic, and came 75 to a package for a dollar. I want to say it was the 99 Cent store, but I visited a couple of dollar stores that day.

2. Thanks. We don't have a 99 cent store but I'll check some of the other dollar stores here.

4. Great idea! Thanks for sharing!
Sherri

1. You're welcome!

5. SUPER idea! Thanks Donna!
Amy Burton

1. You're welcome, Amy. Do you go back soon?

6. I love this, thank you!! I can't wait to use this with my first graders :)

Kelly

1. They should love it!

7. Going back to kindergarten after 5 years away! This will be perfect! I am one of you newest followers! Thx!
Sara

1. Ooh, have fun with the Kinder babies! I'm following your blog now, too. :)

8. Donna- I'm still rootin' around your site (love it!), but do you have some fun ideas for decomposing numbers at 5th grade??
Thanks!
Mickie
mbarrett@nsd131.org

1. Hey, Mickie. That's a toughie. I think composing and decomposing is more prevalent in the primary grades to lay the foundation for what they'll be doing with the skill in the upper grades. For example, when you regroup to subtract, you need to have an understanding of decomposing numbers. Or when you use the area model for multiplication, you're using what you know about decomposing. Of course, you can still do a number of the day and have kiddos find different ways to make the number. And in place value, it's important for kiddos to know that numbers can be decomposing into different groups of thousands, hundreds, etc. I'll think about it and see what I can come up with. :)

9. Found you through Pinterest, thanks for another way for composing and decomposing practice!

1. You're so very welcome! :)