“Reversed” Ages

A simple situation with a mother and daughter’s ages leads to many questions and interesting observations.

In August, at a summer board meeting of the Adult Numeracy Network, the fabulous Sarah Lonberg-Lew (@MathSarahLL) shared a problem. Well, it wasn’t really a problem, more like something she noticed. In the meeting, she asked what we noticed and what questions we might ask.

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Penny Collection

Solange led us in a meeting about teaching mathematics with a focus on discovery, investigation, and student thinking.

In this meeting, Solange presented us with the following problem:

Consider a collection of pennies with the following constraints:

When the pennies are put in groups of 2 there is one penny left over. When they are put in groups of three, five and six there is also one penny left over. But when they are put in groups of seven there are no pennies left over. How many pennies could there be?

Thank you to YouCubed.org for the problem.

Can you help us out? Can you find a solution? Can you find more than one? What strategies are you using?

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Playing with Prime Factors

Starting with a colorful visual representation of numbers, we looked at a series of problems based on prime factors.

For the last few months, I’ve been working on study materials on exponents and roots. While doing research for the packet, I started to get interested in factors and especially prime factors. It turns out that they are really useful for thinking about lots of different kinds of math that we have been looking recently. For example, the mathematics of bicycle gears or Spirograph both have to do with factors, as do fractions, place value, exponents and other math that is relevant to math teaching in adult literacy.

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Exploding Dots

Sophie gave us an introduction to the strange world of Exploding Dots, which can be used to represent all kinds of math. We started with place value.

In July’s evening CAMI meeting, we met an interesting machine, the “two one” machine, written like this: 1<–2 machine.

Here’s how the machine works:

We can add dots to the box on the far right – as many as we want! Whenever there are two dots in the same box…

…they EXPLODE!

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A Strange Algorithm

In our first evening meeting, Eric shared a web site that turns pairs of numbers in diagrams. But how does it work?

(This meeting was based on an underground mathematics lesson, Fawn Nguyen’s post and Michael Lawler’s videos. Thank you all!)

I started the meeting by showing the group the Picture This! web site that turns pairs of numbers into a diagram visualization. I asked for a volunteer to give me two numbers, each less than 10. The first suggestion was 3 & 7. I entered the number into Picture This and this diagram was returned.

3 & 7

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Factor Towers

Eric shared activities from a draft lesson on factors, multiples, primes and composites. The lesson is linked in the post if you are interested in using the materials from the meeting. He would love feedback if you use it with a class.

Launch

To start off the meeting, Eric put us into groups and gave each group a bag of paper tiles. He asked us to spend a few minutes looking at them and discussing anything we noticed.

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CAMI Roadshow: 2018 NYC Adult Basic Education Conference

NYC CAMI revisited the Grid Power problem and modeled the collective problem-posing/problem-solving process of CAMI meetings.

At this year’s NYC ABE Conference, Jane, Eric and Mark brought back the Grid Power problem from the summer 0f 2016.

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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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