Community of Adult Math Instructors (CAMI)
teachers learning math together
Sarah Lonberg-Lew of the Adult Numeracy Network and SABES joined us from Gloucester, MA to lead this meeting with me (honestly, I did very little). We explored a diagram that Play With Your Math calls factor graphs. They got the idea from Things to Make and Do in the Fourth Dimension, by the mathematician and educator Matt Parker. (Check out Numberphile for some of his videos.)
The week before the meeting we sent out this teaser:
Annie Perkins is a middle school/high school math teacher in Minneapolis, MN and she has been sharing a daily math art challenge every day since the governor’s made the call for everyone to stay at home. As I write this, we are going on Day 19.
Continue reading “Math Art Challenges”Have you ever thought about why some fractions turn into decimal representations that go on and on, while others terminate?
Andrew started by describing two kinds of decimal representations of fractions:
Three very different visual solutions were shared in response to a problem about dividing 2-digit numbers.
This was our first online meeting (made necessary by the COVID-19 outbreak). It was a great distraction and made it possible for Adult Numeracy Network friends to join us from the Hudson Valley, Massachusetts, and Wisconsin. Our meetings for the next few months will almost certainly be online, so join us if you’re able.
The problem for this meeting came from Math with Bad Drawings and @mathsjem before that:
Continue reading “Dividing a 2-digit number by the sum of its digits”Nice little puzzle pic.twitter.com/qh7FCkcjLN
— Jo Morgan (@mathsjem) October 22, 2019
Solange shared some card puzzles and tricks that she has been playing with. Our job was to figure out how they worked.
The first card “trick” (more of a puzzle, really) was from Marilyn Burns’ blog. It’s called the 1-10 card investigation.
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.
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?
Continue reading “Penny Collection”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.
Continue reading “Playing with Prime Factors”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!
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.
