Teaching

A common debate in math education centers on the extent to which students should memorize things, like multiplication tables, the quadratic formula, or the division algorithm.

There are many sensible arguments against memorizing algorithms. While memorizing algorithms might produce good results in a typical math class, mathematics makes the most sense when it is understood as a coherent, interconnected system of thought. We want students to be resourceful and creative problem solvers, and this requires that students understand the context and the connections, not merely the steps, of the procedures they learn.

Occasionally this argument is taken to the extreme and teachers altogether discourage memorization of algorithms and procedures, claiming that it’s pointless for students to have the procedural knowledge without understanding the context.

While there is some merit to this argument, I was recently reminded how valuable it can be to blindly memorize algorithms.

A friend invited me to go rock-climbing, something I had never done before. We arrived at the gym, and my friend, an experienced climber, showed me how to identify the beginner trails on the wall and encouraged me to get climbing right way. Over the next hour I attempted a few trails, and met with more frustration than success.

After a particularly discouraging attempt, I sat down next to my friend to rest. He told me that he noticed I was getting stuck in the middle of the trail and was having difficulty finding the next hold. He suggested that I examine the trail before I start the climb and memorize the sequence of moves needed to make it to the top.

By memorizing the wall-climbing algorithm, I was freed from trying to do too many things at once. I could focus on developing the fundamental techniques — proper holds, balance, body position, different reaches — without worrying about what the next step should be.

Ultimately we want the ability to be on an unfamiliar wall, or in an unfamiliar problem, and have the confidence and skill to figure out what to do next. But this skill is really a combination of many skills, and it can be challenging, and frustrating, to try to develop them them all simultaneously.

Sometimes memorizing things — like a sequence of handholds, or the quadratic formula — can help us get to the top. And it can help prepare us for the day when memorizing won’t be enough.

This beautiful image is this year’s testament to trying new things and giving vague directions.

At the end of every school year I challenge myself to do something brand new in each of my classes. This could take the form of new mathematical content, a new kind of project, a novel technology, or something else entirely. What’s important is that it’s something I’ve never done before.

In this year’s Calculus courses, that new thing was Sage Mathematical Software. To get students familiar with plotting in Sage, I presented them with a mundane task. I gave them code that defined a square region in the plane and asked them to play around with some of the parameters to create a new graph, which they would then post in our class forum.

Naturally, I provided an example of what they might do.

Having never done this with students before, and being a novice with the software myself, I didn’t really know what to expect. I suppose I expected students to produce graphs similar to what I had done. They didn’t.

They played around with the functions, the colors, the domain and range. They inserted cotangents, exponential functions, and additional constraints. They found options for the region_plot function I didn’t know existed. I expected them to produce graphs of boring quadrilaterals, and instead, they produced beautiful, complex, and intricate contour maps like the one seen above.

This is what can happen when, instead of telling students to do A, B and C, you give them vague, open-ended directives like play around and share. More often than not, students rise to the occasion and create work that surprises and amazes. And this reminds us to keep trying new things in the classroom, if only to create opportunities for students to defy our expectations.

You can see more of the beautiful, diverse images the students created here.

Preliminary applications for the 2013 Rosenthal Prize for Innovation in Math Teaching are due Friday, May 10th.

The Rosenthal Prize, presented by the Museum of Mathematics, is designed to celebrate and promote the development and sharing of creative, engaging, replicable math lessons.  The author of the winning activity receives $25,000, and the lesson will be freely shared with teachers around the world by the Museum of Mathematics.

Although May 10th is fast approaching, this first deadline is just a preliminary one.   If the application process is anything like last year’s, all that is required at this early stage are a few short essays about teaching philosophy and the overviews of the lessons you intend to submit in the fall.  If an applicant passes through the preliminary stage, a more comprehensive application portfolio will likely be due in the fall of 2013.  Again, this assumes the process is similar to last year’s.

If you’ve got some fun, engaging, and replicable math lessons to share with the world, consider applying for the Rosenthal Prize!  More information can be found here.

I am proud to be featured in the Roots of Unity blog at Scientific American.

Evelyn Lamb’s piece, “Award Winning Teachers Put Math on Hands and Heads“, reports on the inaugural Rosenthal Prize for Innovation in Math Teaching, presented by the Museum of Mathematics.

As runner-up for the Rosenthal Prize, I was interviewed for the piece, and had a chance to talk about my teaching philosophy, my award-winning lesson, and the value of hands-on, collaborative activities in mathematics class.  In summarizing my approach to teaching mathematics, I said

“I want the classroom to be a place where we explore ideas together, where students can play around, experiment, collaborate, argue, create, and reflect on everything.”

The purpose of the Rosenthal Prize is to encourage and promote innovative, replicable math activities that engage and excite students.  I’m honored to be a part of this endeavor, and I look forward to more fun and creative math lessons being shared in the future.