Race for 20―A Counting Game for All Ages



Saturday, March 28th, 2020
Looking for an easy-to-play game that requires only the ability to count to 20, but has a real mathematical kick? Here it is. Teach it to your kids at home or to your students online to play with someone at home. Read on for the rules and some tips, including how to tweak the game to keep kids interested and challenged.

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Riddles That Rhyme (not entirely a math post)



Tuesday, March 24th, 2020
Riddles are usually a hit with kids, and with many at home and sheltering in place (as I am), diversions can be helpful. When rummaging through my book shelves, I found a book that I wrote in 1981―The Hink Pink Book. I wrote it shortly after I first learned about Hink Pink riddles, and also about Hinky Pinky and Hinkety Pinkety riddles. I think these riddles are good for some language play for kids at home, with a little math thrown in.


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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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