I was in a training today and they had us solve a Van de Walle problem called One Up, One Down. It goes like this:
When you add 7 + 7, you get 14. When you make the first number 1 more and the second number 1 less, you get the same answer. (Van de Walle, Karp, and Bay-Williams, 2013, pg 17)
Our challenge was to determine if this would always work for doubles and if it would work for situations where the addends are not the same. We had to have a representation to show our thinking. The different representations that people came up with were very cool! Here are a few…
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A ten-frame representation |
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Using counters as a model |
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An addition/subtraction chart |
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Yikes! Big math! |
Awesome activity, don’t you think? Enjoy your weekend!
So cool! I love mathematic!
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Hi Donna! Overtime I link to your site the images don’t appear. When I click on them a window pops up saying “page not found”.
I don’t know, Yasmine. But thanks for letting me know. I’ve fixed this one.
This one is cool! Thanks!
I know! I thought it was pretty neat the different representations we came up with. A great problem to use with kiddos.