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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A Mental Math Lesson



Tuesday, June 2nd, 2015
I asked a class of fourth graders to figure out the answer to 99 + 17 in their heads. In this post, I describe why I chose that problem, include a video of how the lesson unfolded, describe a teaching error I made in a subsequent lesson, and more.


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We Ask, We Listen, We Learn



Monday, January 5th, 2015
How much is 12.6 × 10? This is a question from the Math Reasoning Inventory (MRI) decimal assessment. What do you think were the most common incorrect answers given by the more than 7,800 students who figured out the answer in their heads? And what about the boy who answered, “One hundred twenty and thirty-fifths?”


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