Friday, March 28, 2014

Desmos Art: Fries

The Assignment

1.  Draw a design using only straight lines. 
2.  Snap a photo of your drawing. 
3.  Import your photo into Desmos
4.  See if you can duplicate your drawing using linear functions.  


We looked for two things: challenge and precision. We got anything from a simple right triangle to a box of fries.  Anything with 3 or more lines intersecting at the same point proved to be very challenging; 2 lines fairly challenging; no intersections...not so much.  

Precision was key.  They could fool themselves as long as the grid, axes and labels were turned on.  But once those things went away, it was just lines drawn (with pencil or graphs) by students.  

I created a filter that contained the words "shared a graph with you" that dumped the graphs students emailed directly into a folder labeled "Desmos Art."  I used SnagIt to take screenshots and highlight areas of the graphs that needed feedback and sent the screenshots back to students.  It was a pretty nice workflow, actually.

Student Feedback
Most students noted that they started out thinking this assignment was really hard--that they couldn't do it. Then they got their first line to match. The second line was easier then the first; third easier than the second , and so on. Domain restrictions turned into range restrictions for vertical lines and some learned really quickly that it was easier to restrict the range for really steep lines.  

The perseverance I saw in students makes this one a keeper.