Category Archives: Geometry

When I Let Them Own the Problem

From our textbook: Stuff like this makes my heart sink. (I actually wrote that it makes me fart — but that’s very unladylike. And I’m trying to write better.) There is essentially nothing left in this problem for students to explore and figure out on their own. If anything, all those labels with numbers and variables […]

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Students Embroiled in Conway’s Rational Tangles

Me: We’re going to do an activity today. Jonathan: Let me guess. It’s your favorite activity. M: How did you know that? J: You say that about everything we do. M: You have a problem with that? J: No. But I’ve lost track of how many favorites you have. M: And I’ve lost track of how many […]

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Don Steward’s Complete the Quadrilateral

This activity is from Don Steward’s post Complete the Quadrilateral. I’ve only learned of Don’s MEDIAN site more recently, and it’s a treasure trove because nearly every post can be an instant lesson in itself. Thank you! I like this set of 24 problems a lot, but when I click on the image of the problem in his post, I […]

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The question was mine, but the answer was all his.

I carry a defective teacher gene that makes me intolerant of pacing guides and curriculum guidelines. I’m sure I’m a month behind in the pacing guide, and I’m pretty sure no part of today’s lesson will appear on any state test. But I did it anyway. The algebra kids have been doing a lot of […]

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Equilateral Triangles

Thank you to Dan Meyer for this great task idea on equilateral triangles. Act One is this video which asks for a ranking of how well each teacher had drawn his equilateral triangle. But as soon as I saw the video, two thoughts came up: We’re in a 0:1 classroom right now, and having the whole class come […]

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Sharing My Favorite Math Books with Students

In my next life I hope to be able to collect pretty shoes the way I’m collecting math books in this life. Of course I haven’t read them all. Not even close. But just seeing them on the bookshelf makes me happy. A good book is nothing if not shared. I always share some of my favorite […]

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Three Geometry Lessons

1 I love this assignment (from NCTM, I think). The kids shall too. So this front page of congruent_halves is for their final recording. In addition to the extra copy for them to mess around with, you can also give them dot paper to copy the shapes and investigate further. No cheating, see if you can figure out […]

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Mr. Meyer’s Taco Cart

Won’t be long before I have to change the post title to Dr. Meyer’s Taco Cart. This lesson went really well today. Act 1: We watched the video clip. Their guesses: Me: That was fun. Kinda split in the middle there with your guesses. But that question of who gets there first only gave you two choices, […]

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Foxy Fives – cuz it’s better than Four Fours

Foxy Fives is my Day 21 lesson (actually a game) that I got from this book. The teacher is supposed to make a deck of 62 cards from posterboard, the cards are marked from 1 to 25, and blah, blah, blah. For the life of me, I don’t know why you’d need a deck of cards at all […]

Also posted in Algebra, Course 1 (6th Grade Math), Problem Solving | Tagged , , , , | 3 Responses

Two Lessons: Frog Leap and Beach Ball

I call it Frog Leap but you may know this common game as Stepping Stones or Traffic Jam. NRICH has a nice interactive applet. The challenge is for the 3 boys and 3 girls to switch places in the FEWEST moves possible. A legal “move” is each person can jump onto an adjacent empty space or jump […]

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