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Little People

The last time I effectively taught adding & subtracting with negative numbers I was on to a good idea, but there were a couple of faults – only the kids actually walking the number line were engaged, and they lost their positional cues as soon as they went back to their desk. So this time, […]

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So I signed up for that better lesson thing. And I’m not using it. Take this recent lesson from my pre algebra class, for example. The obvious WCYDWT is fractions. The trick, what made my lesson work, is that I had kids figuring out how many people you could split it between, smallest number you […]

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I should be able to gauge this, but I have no idea if this is going to be too easy, or too hard, or just right for my geometry class as a warm up tomorrow. It’s not that it’s a bad problem – it’s that I can’t get the level of challenge right. I’m not […]

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Making them think

My kids are very answer oriented. I can tell them to focus on the process, but as any decent teacher knows, telling isn’t learning. This is probably old news to some of you out there, but I’ve finally found a way to get my Geometry kids to focus on the process more than the answer: […]

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Identifying perfect squares

I’ve been doing the distance formula in Geometry this week. I started it off with an accelerated version of my 7th grade pythagorean lesson. Basically, a quick discussion of this applet, followed by the second worksheet from this post, and finally the application to to the coordinate plane. It was a great lesson. There were […]

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The Factoring Puzzle

Jason put up a very cool puzzle that is equivalent to solving a quadratic equation. Somewhat spurred by a comment on that post, and partly out of my own confusion as to what was going on, I tried to make up my own variation1: Some of my students, once the understand the relationships between the […]

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What I’d do with this

Following up to my previous post: I have a couple of observations on this. The first is that the populations we teach can strongly affect how we think about developing lessons. My students are poor estimators – In class discussion they’ll yell out numbers without any thought, hoping that they just guess right. I’ve made […]

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What can you do with this?

I’m boldfacedly stealing this idea from Dan. I’ve got my planned lesson (and the eventual overlay) but I want to hear your ideas first.

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Unconventional Construction

So I threw the triangle congruency rules at my kids. Being smart kids, they dutifully memorized them, and some even figured out what they meant. Kind of. But they didn’t get it. It’s the sort of thing you want to use construction for – to let them dig in and experiment and try for themselves […]

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Copying Lines

For all of their hatred of numbers in their various forms, kids really struggle with graphing. Something I tried this year, and will expand on next year, is to just have them copy graphed lines off of my slide onto their xeroxed worksheet of grids. As I went around, I gave a running count of […]

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