Sidewalk Chalk

I have been teaching long enough to know that as soon as the weather starts getting nice, students start getting restless. It doesn't matter how old they are, and it doesn't matter what the context. My college students get as restless as my high school students did. On one of the first really beautiful, warm, sunny spring days this year, one of my students came to my office hours to show me his homework and said, "I have to be honest. I'm not coming to class today because it's just too nice to stay indoors." With some students such a comment might annoy me (I don't want to stay indoors either on a day like that - sometimes you have to make sacrifices). But he's a good student, and consistent, and frankly I understood where he was coming from.

It is very rare for a spring semester to pass without students asking if we can hold class outdoors. They know it's wishful thinking. Sometimes I see classes out on the lawn, and at Washtenaw it's especially tempting because there's an outdoor classroom right outside the door to the building I teach in. There's a rock podium and several rows of large boulders for students to sit on, and I would love more than anything to be able to take my class out there. But unfortunately, math is a hard subject to transport outside. You need the visuals, and there are not chalkboards in the outdoor classroom.


This past week, though, I had the chance to make my students' dream come true. On Wednesday I was getting materials ready for our class on addition and subtraction of positive and negative numbers. Because most students know (or can easily re-learn) the basic rules of addition and subtraction of integers, I try to focus on number sense, and visualizing numbers and operations and distances on the number line. The activity I use involves moving a stick figure along a paper number line, but when I went to dig out the laminated stick figures from last semester, I had a brilliant idea. It seemed that it would be much more effective for my students to play the role of the stick figure, and to walk the number line themselves.

So I procured myself some sidewalk chalk, and after their quiz, I had my students pair up, take a piece of chalk and a sheet of instructions, and head outdoors. They drew long number lines on the sidewalk and I told them to forget everything they know about integer arithmetic and to take steps along the number line to figure out a series of arithmetic problems that I had chosen for the purpose of helping them visualize certain patterns and rules.


I was pleased with how my students bought into the activity. I don't know if they all learned what I intended them to learn from it, but I think they got more from it than they would have with the paper cutout version. And after they had been working for awhile, I had them congregate at the circle of stones out in front, and I got to fulfill my own dream of teaching in the outdoor classroom. This may be the one and only chance I ever get to hold class outdoors, but I had fun doing it.