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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Teaching Adding Decimals: What If You Give the Answer First?



Sunday, January 14th, 2018
When teaching students to add decimals, I wind up reminding students to “line up the decimal points.” This makes sense to some students while others follow the rule without understanding. How can we teach adding decimals to develop understanding and skill? Here’s a possible suggestion: Give the correct answer up front.

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When Should and Shouldn’t We Give Answers?



Sunday, February 5th, 2017
Over a year ago, I blogged about The 1–10 Card Investigation. I didn't provide a solution to the problem and no one who commented asked for one. But a newly posted comment requested the solution. That pushed me into a conversation with myself about how I should respond, and about giving answers in general.
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One Lesson, Three Grades, Three Twists



Monday, January 30th, 2017
The children's book 17 Kings and 42 Elephants by Margaret Mahy is one of my long-time favorites. In this post I describe a division lesson that I’ve taught to third graders but recently revisited with fourth- and fifth-grade classes. With the older students, we tried extensions that differentiated the experience and put students in charge of deciding on problems for themselves. It was exciting to me to expand a lesson I've taught many times into a multi-day investigation.



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Always Try a Problem Before You Assign It



Wednesday, September 14th, 2016
Have you ever thought about this numerical sequence—0, 1, 2, 3, 4, 5, 7, 8, 10, 12? What does the sequence have to do with unicycles, bicycles, and tricycles? And what's my mathematical and pedagogical quandary? Read more and find out.

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