I really enjoyed today’s “First Day” activity in Precalculus. I found the idea on Becky Lyon’s blog; you can also find her on Twitter: @rhlyon.

I had the students find someone to work with and told them one member of the pair would be the **Explainer** and the other would be the **Grapher**. The Explainer was supposed to sit facing the projector screen, while the Grapher was supposed to sit facing the door (i.e., *away* from the projector where they could not see it at all).

The idea of the activity is this:

**Display**a picture or graph on the projector screen for about one minute.- The Explainer has to
**describe**the graph only using words — no hand gestures allowed! - The Grapher tries to
**re-create**the picture or graph from the description.

The pictures I used started out easy (a giant smiley face) and got progressively more difficult. To give you an idea, I uploaded the exact graphs I used to my public Dropbox space: It’s http://dl.dropbox.com/u/59433434/111-Day1.pdf. After we were done, we went through the graphs together and talked about what descriptions had been given and what people *could* have said to make it easier.

This gave us a great opportunity to review vocabulary like “**degree**” and “**vertex**” and “**parabola**” and “**quadratic**” and “**intercept**” and “**slope**” and “**local maximum** [versus global maximum]”. It also gave me feedback as to what the “groupthink” occurred and at what level my students are starting. (For instance, some of them volunteered the idea that an **even-degree root of a polynomial** behaves differently on a graph than an odd-degree root!)

They seemed to enjoy the activity. It helped cement for them that I will expect them to *do* things in class, not just *be*. And, happily, it gave them the opportunity to practice my Friendship Policy.

My three favorite comments from today include:

- “
**This will be the most FUN class!**” –a student said to her friend, at the end of class - An e-mail I received after class said, “
**What a great first day of class! Super exciting and thank you for your approach!**“ - A fantastic Tweet (admittedly from a calculus, not precalculus, student):

**Not gonna lie, My calc prof (**~~@~~katemath) scares me a little. But I think that’s why I’m gonna love the class.— Dalton Sligh (@daltonsligh) August 22, 2012