## Sunday, April 20, 2014

### A Common Core Alg Activity Using Desmos - Piecewise Linear Functions and Squares

This is my first attempt to use Desmos, the outstanding free online graphing calculator (and a free iPad app). I'm sure many of you have been utilizing this powerful resource. There are already many available teacher samples you can use.

CLICK ON THE GRAPH TO LOAD THE APP.

Let me know if you can view the graph (you may have to adjust the window slightly). More importantly, what do you think of the activity and do you see its potential for deepening understanding of algebra?

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fivetwelvethirteen said...

This is awesome! I just finished. I really like how Desmos makes this activity much less low-risk -- students can try a function and adjust iteratively until they find the right linear equation/domain, and since they get three chances to graph a side of the square they have a chance to figure out more efficient ways to identify the function and identify patterns and connections.

It's also so critical to synthesize graphing, slope, intercept, and domain into questions like these that are grounded in a context where students can check to see if their answer makes sense right away.

Dave Marain said...

Thank you so much for this support! I'm an educator first and a technophile 2nd. If the technology can enhance and deepen conceptual understanding then it makes sense to me. Desmos has this potential and this was my first attempt. I've developed activities like this in the past starting with graph paper , then onto TI. It is important for me to say that the PROBLEM preceded the technology!

I saw the interactive/feedback advantages you picked up on and my instincts told me this could work. As I continue to work with Desmos and learn from others' examples, I'll get better.

The learning curve for Desmos does not appear to be that steep here. Inagine if each math teacher were to contribute just one activity!

There are some features I'd like to see that may come with updates, e.g., involving setting ranges for tables, but, hey, it's early!

Thanks again...