What Is 5 Divided by 4? So Many Answers!



Wednesday, February 27th, 2019
Fourth graders solve the problem 5 ÷ 4 in the context of sharing cookies, figuring out how to share five cookies equally with four people. The students came up with six different solutions―all of them correct! (Try and think of what they might be before continuing to read.)



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Algorithms Are Not Enough!



Tuesday, February 19th, 2019
Last year, I agreed to meet with a friend’s sixth-grade son. Oscar’s math teacher had raised an alarm for my friend and her husband about Oscar’s math progress. They were shocked. Oscar did his homework and was proficient with paper-and-pencil math. What was the problem?

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When You Multiply by 10, Just Add a Zero? Horrors!?!



Monday, October 1st, 2018
Have you ever asked students to solve 12.6 x 10, and they respond that the answer is 12.60? I have, many times. Students who do this apply a pattern that works when they multiply whole numbers by 10—they tack on a zero to the end of the number they’re multiplying. But then they apply the same pattern when working with decimals. What can we do?
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Can 1/3 + 1/3 = 2/6? It seemed so!



Thursday, March 22nd, 2018
I thought I was on the right teaching track using real-world contexts to talk about fractions with a class of fourth and fifth graders. Then a surprise occurred! I’m still mulling over what I could have done. I’d love your thoughts.



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