My surprise afternoon with the MTBoS and MAA President Francis Su

The NCTM annual meeting was in Boston earlier this week. I’d reached out to Fawn Nguyen and Dan Anderson to grab lunch since we’d never met in person, and we eventually decided to meet at the MTBoS booth at the end of the conference. The choice to meet there led to several amazingly fun and lucky breaks.

One was that I got to meet many of the people who share great math on Twitter including Tina Cardone, Justin Lanier, Jasmine Walker, and, since this was the Math Twitter Blog-o-Sphere, here’s one twitter handle only just for fun: @Mythagon.

Another great thing that happened was that Francis Su, the president of the Mathematical Association of America, happened to stop by the booth at roughly the same time I showed up. I don’t know what (if any) connection there is between the MAA and the NCTM, and maybe the MAA’s president is at the NCTM annual meeting every year, but I thought it was pretty cool to see him there interacting with so many math teachers. Tina Cardone gave him a copy of her book – Nix the Trix – which is a sensational example of teachers working together online to improve math education. He seemed genuinely interested and I really hope he enjoys reading through it.

Here’s a tweet with everyone at the booth when the conference closed:

We all ended up going to lunch together and Francis and I ended up talking about several of the amazing math resources that are on line for both pre-college math and popular math (for lack of a better phrase).

I mentioned seeing a Numberphile piece in which Ed Frenkel lays out his vision of math education and then seeing Dan Anderson’s amazing “My Favorite” blog post. I wrote about both of those things here:

A list Ed Frenkel will love

Obviously Fawn Nguyen’s writing (and tweeting!) has been hugely influential to me. Her twist on the classic picture frame problem was one of the first things that I saw from her and I was absolutely blown away:

Fawn Nguyen’s amazing picture frame project

Actually, having been lucky enough to have Fawn introduce me to Math Forum folks this weekend, I remember another really great project inspired by Fawn tweeting about one of their problems:

Fawn Nguyen shares a really neat Math Forum problem

With all of the amazing sharing from teachers online, I guess it isn’t so surprising that the project that I did with my kids today came out of that post-lunch conversation with Fawn at the conference center:

A great problem from Chris Hunter and Fawn Nguyen

After discussing the sharing from teachers, we talked about some of the great accessible / popular math that is being shared online right now, too. Numberphile, for example is doing an amazing job. Their presentation about the Pythagorean theorem with Harvard’s Barry Mazur, for example, is incredible:

Using Numberphile’s Blob Pythagoream Theorem video in a lesson

Their video about the sum 1 + 2 + 3 + . . . . is one of the most viewed math videos anywhere online:

Of course, the popular sharing often has quite a bit of overlap with what many teachers are sharing. One of our first blog projects was inspired by a Numberphile video shared by Dan Anderson that reminded me of an old Patrick Honner blog post:

Numberphile’s Pebbling the Chessboard game

Finally, there are some great popular math talks by some really famous mathemtaticians, too. Terry Tao’s “Cosmic Distance Ladder” presentation at the Museum of Math is an absolute must watch and inspired 3 different projects with the boys. It is incredible to me that this Terry Tao lecture has been seen only 2,500 times:

A collection of project from Terry Tao’s MoMath talk

Also Jacob Lurie’s Breakthrough Prize talk is a wonderful introduction to mathematics:

Using Jacob Lurie’s Breakthrough Prize talk with kids

It really is a great time to be involved in math!

So, a super lucky day for me yesterday meeting so many of the teachers that I follow on twitter, meeting Francis Su, and then spending the rest of the afternoon talking with Fawn and still more teachers. What a great day to have been in Boston!

A great problem that Chris Hunter and Fawn Nguyen showed me yesterday

Had a fun time yesterday showing up at the end of the NCTM conference in Boston. What was originally a plan to grab lunch with Fawn Nguyen and Dan Anderson turned into a full day of meeting tons of people I’d only known online.

Over drinks at one of the bars at the conference hotel, Chris Hunter and Fawn showed me a really cool problem from Chris’s blog:

Chris Hunter’s blog

The problem is pretty easy to state – you and two friends go to the store to buy shoes. You have a “buy 2 get one free” coupon that allows you to get the lowest price pair out of 3 pairs for free. The question is what is the fair way for the three of you to split the savings?

I was so excited to try out this problem with the boys today that I stole the napkin that Fawn was writing on!

Math Pic

It seemed like the best way to go through this problem was with each kid individually. I started with my younger son. He had a little bit of trouble understanding the problem (so this video goes about 7 min) – the cost savings combined with the free item confused him, for example. However, with a few little clarifications he was able to get to an answer that he thought was fair.

Next up we looked at a similar problem with different numbers. These numbers present a new issue to deal with if you want to split the total price equally. This second problem also served as a great way for my younger son to get a little more clarity on some of the previous parts of the problem that had confused him.

Next up was my older son. His initial focus was on everyone paying the same amount, but after thinking about it for a little bit longer the equal split idea started to bother him. He wasn’t sure what a “fair split” meant. He thought for a while about other fair ways to split the price and eventually found the idea of splitting the savings. That thought process shows what I really like about this problem – lots of opportunities for thinking here and no obvious “right” answer. At the end, though, he thought splitting the total price equally was the most fair.

The neat thing about my son’s conclusion in the first problem is that it set up the next problem perfectly. If we split the total price equally in the second problem, there’s a strange issue for one of the three people. It takes him a while to notice the problem, but when he does notice it he thinks that the “splitting the savings” here is the fair way.

So, definitely a great problem for getting kids to talk about math. I really like the idea that different people are going to have different ideas about what is fair here, and I imagine those different ideas would lead to some really fun debates in a classroom setting.