## Line Rider Fun (or McDonald’s does Calculus)

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Last year a few of our students discovered Line Rider — a computer game in which they could draw paths and a little sledder guy slides down and up. It’s a fantastic application of tangent lines (and therefore calculus with perhaps some vectors and physics), because in the version that I saw them doing last year they would simulate a curve by drawing lots of straight lines, as in this 83-second video:

It looks like Line Rider has gotten all fancy now (or maybe the artists are just more experienced) and you can draw curvy lines for the little guy to slide on. This inspired the following 30-second McDonald’s commercial:

Because calculus is so important, Line Rider has also been released for phones (Mobile in August and, according to a news release this past week, the iPhone and iPod Touch this month). No need to be without it ever!

Have you ever noticed how mathematicians count pretty much everything as applied mathematics? Yeah, I know, looking at the world through math-colored glasses!

### 3 Responses to “Line Rider Fun (or McDonald’s does Calculus)”

1. Dave Says:

Yes, all summer I’ve been trying to think of a good way use this in my calculus class. Any ideas?

2. Ξ Says:

When I introduce tangent lines there are always students who can’t “see” what they look like. The earlier(?) version of Line Rider, like the first video, uses straight lines so I think you could show that and have them “envision” the curve from the tangent lines.

Likewise, since the derivative measures the slope of those lines, you can use it to illustrate that the slope of the curve changes.

(OK, so it’s not really deep. But as a single example, it’d be kind of cool to show it!)

Maria Anderson (from the Teaching College Math Technology Blog) explains here that she has a video that illustrates two different kinds of discontinuities: hole [where the guy sleds over it] and jump [where the sledder changes levels].

3. Dave Says:

Thanks! I’m teaching about continuity right now–I think I’ll use Linerider to show them removable discontinuities, jump (ha ha) discontinuities and the dreaded (for the sled rider) vertical asymptote. The students will have fun with this, I think. It is silly, but concrete, visual, and memorable.

(I’m not sure if Ill be able to pull off sin(1/x)….)