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Applications are Open for Cohort 4 Fellows

Twitter for Shelley CarranzaShelley Carranza
| February 01, 2019

Group portrait of Desmos Fellows and staff at last year's Fellows weekend Applications for Cohort 4 of the Desmos Fellowship are now open, and we think you should apply! Here’s what our current Desmos Fellows are saying about the Desmos Fellowship:

  • Desmos Fellows weekend was the most amazing professional development I have ever experienced as a math educator. It is difficult to find PD that is a room packed with people so passionate about how we help students learn math and how the technology of Desmos has completely changed how we can do it.
  • Desmos Fellows are the math department we all dream about. Supportive, collaborative, caring, and innovative. I strive to create experiences that parallel the experience I had over the Fellows weekend. I didn’t want it to stop and although the weekend did, the support didn’t.
  • I was so grateful for all the Desmos knowledge I gained, but more than that I was inspired by the exceptional collection of math teachers. The fellowship felt more personal and impactful than any other PD I’ve attended. The weekend created long lasting connections, both mathematical and professional.
What is a Desmos Fellow, you ask? Desmos Fellows are curious learners and avid explorers of the territory where math, teaching, and technology meet. They draw on their unique backgrounds and experiences to contribute to the Desmos Fellowship and beyond! As a Desmos Fellow, we’ll fly you out on an all-expenses paid trip to Desmos HQ in San Francisco from July 12-14, 2019, for a weekend of learning and community building. You’ll take all of those tools and ideas back to your schools and districts, energizing your own practice and that of your colleagues. We hope the Fellowship Weekend is just the beginning of your participation in the Desmos Fellowship and your collaboration with the Desmos Faculty.

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Friday Fave for January 25

Twitter for The Friday FaveThe Friday Fave
| January 25, 2019

Let’s say you want to draw a line segment that connects two movable points. You can write your line in point-slope form, use the changing coordinates of the movable points as parameters in the equation, restrict the domain, and you’re good to go.

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But what about when the point on the right becomes the point on the left? Now your domain is bad so you need a workaround. Easy peasy—just make a second line segment with the domain restriction switched: less than becomes greater than and you’re back up and running.

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Wait. What if the points are aligned vertically? Now you need a third, and maybe even a fourth expression. That’s a lot of work for a line segment, and it is why you will be delighted to learn about this week’s Friday Fave: parametrically defined curves.

Here’s the idea: You want your line segment to begin at one of the movable points, and end up at the other one. If you can make a POINT do that, like so…

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…then you can use the parameter t to trace out ALL of those points.

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Now it doesn’t matter which point is to the left or the right; and it doesn’t matter if they’re vertically aligned. In the latter case, the x-distance between the points is 0 so the x-coordinate will remain constant for all values of t.

With time and practice, this way of thinking will become natural—make a point move from one place to another, then use t to define the entire path. Pretty soon, you’ll be tracing all kinds of fun paths!
alt text That’s why parametric curves in the graphing calculator are this week’s Friday Fave!