Divisibility Exploration

In this meeting we looked at the divisibility rules for 2, 3, 4, 5, 6, 8, 9 and 10 and tried writing our own rules for larger numbers.

In this meeting hosted at 3rd Avenue VFW by teachers at MDC Brooklyn, we continued recent explorations into multiplication and factors. In this meeting, we looked at divisibility rules. After a pair/share and introductions, I asked the group to look at multiples of 9 and share what patterns they noticed. We shared in small groups then talked about a few things people noticed.

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Thirteen Ways of Looking at Multiplication Tables

Looking for the surprising in the familiar, we see what happens when you look, really look, at the multiplication table and tumble through the looking glass.

I once taught a poem by Wallace Stevens called “Thirteen Ways of Looking at a Blackbird” to a class of adult literacy students. Before I gave out the poem I put the title on the board and asked students what they thought the poem was going to be about. They had all kinds of ideas about looking at blackbirds. Then I asked them, “What about the first part? What does that mean Thirteen ways of looking at a blackbird?”And they said things like:

  • “Thirteen ways to understand the bird is better than one… but you have to take time to see the bird.”
  • “If you look at the bird you will find all the different things it does, but you have to look closely.”
  • “We don’t pay attention to these things and he wants us to focus.”
  • “He stopped to pay attention to something so maybe we will too.”

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Multiple Factors

Several engaging activities for exploring factors. Which would you use for HSE math classes and how would you use them?

I puzzled over what to bring to today’s meeting for days. I have a couple unfinished problems that I’ve been thinking to bring to a CAMI meeting, but in the end I chose to go with a few activities on factors, mostly from Fostering Algebraic Thinking, by Mark Driscoll. A group of us read the book last summer and loved the problems. There were so many good ones that we weren’t able to solve them all while reading the book. I went into this meeting hoping that the surprise of the central problem wouldn’t be ruined. Continue reading “Multiple Factors”

Exploration of Consecutive Numbers

In this meeting, Usha returned to lead an exploration of consecutive numbers through a low-entry, high-ceiling problem she recommends as an introduction to functions/algebra.

For our June meeting, we were lucky to have Usha Kotelawala, Director of Math Education for CUNY’s LINCT to Success, as a guest presenter. Usha started the meeting by talking a little about her thought process in choosing today’s problem. In discussing CAMI with Usha, Eric had raised the issue of how to order problems through a semester, so that the mathematics is sequenced and scaffolded for students and students learn through problem-solving. In response to this question, Usha brought us a problem she recommends as the first in a sequence on algebraic reasoning. Continue reading “Exploration of Consecutive Numbers”

Multiple Ways of Multiplying

We explored multiplication through a number talk and alternative algorithms for calculating products.

Before the meeting, Davida showed Rachel and me a multiplication method a student had showed her earlier in the day. The student said that she only knew how to do multiplication using the method on the right and wanted to learn the method on the left. What a coincidence! This is exactly what I was planning to explore today.

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Slip Sliding Away

A look at the slip slide method of factoring polynomials

Cynthia started by showing us Kahoot, a free and easy way to run a quiz game in class with students buzzing in through cell phones. Kahoot allows you to create surveys and surveys. Students load Kahoot.it through their cell phone and are asked for a PIN. Once a student enters a PIN, they join the game.

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