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Fellows’ Lounge for November 8

This week we invited the fellows to share ways that they are using Desmos for assessment purposes. While many had never used Desmos for assessment, those who had did so in unique and interesting ways. Some examples include:

  • Gerald Smith and Paul Jorgens have considered Desmos for part II of a test, where the topics aren’t as easily assessed on paper. Such is the case for problems that involve analyzing a set of graphs or creating graphs as part of a more open ended problem.
  • Serge Ballif teaches a course that uses Desmos for all exams. Students in his class spend very little time on the mechanics of solving equations, because Desmos will solve for them. Instead the class focus is on setting up equations and models and interpreting solutions.
  • Projects! Sarah Blick Vandivort has her students using Desmos to produce a graph as part of a project on linear systems. Linda Saeta, Anna Scholl, and Jade White have used Des-Art to assess student understanding of equations of lines and other function transformations.
  • Tony Riehl’s students completed their first semester final exam review on Desmos. Access to data helped Tony determine areas where students needed additional review.
  • Nick Corley has considered designing activities to help students practice for the PARCC exam.

Nolan Doyle pushed us mid-discussion to consider why we are using Desmos as an assessment tool, and to be purposeful in choosing ways to incorporate it. He wants his students to view Desmos first and foremost as a tool to help them explore math and make discoveries on their own, and wonders if students may view Desmos differently if used on assessments.

Some of the fellows are using Desmos on both formative and summative assessments in order to collect and learn from the data. Paul Jorgen’s PLC routinely uses data from activity builder dashboards to assess student understanding of topics and decide on activity revisions and next steps. Scott Miller noticed through looking at data that analyzing the graph responses helps clarify what misconceptions students have around more open ended tasks.

Even with the ease of collecting data, many of us wondered about logistics. Julie Reulbach shared her midterm with us, which included a mix of responses submitted on paper and on Desmos. Another idea for logistics and test security was to keep test problems on paper and have students submit answers only in a Desmos Activity.

What ideas have you tried? Let us know on Twitter @desmos.

Friday Fave for November 4

Playing Catch Up is a modern update of Tortoise and Hare. Sportscaster Rich wears a suit and plays the role of Hare. Wide receiver Julio surprisingly plays the role of Tortoise, but only because the magic of video has slowed him to half speed.

Who will win this Des-race?

Students predict when (if ever) Rich catches half-speed Julio. We invite them to consider how graphs, tables, and equations provide different kinds of information, and are useful in different ways for making this kind of prediction.

The part of the lesson that excites us the most is the reveal, which again takes advantage of our new video tool in Activity Builder. Students watch the finish of the race, and see whether/when Rich cases Julio.

We do not tell students the answer (and neither should their teacher)!

Instead, we give them the video evidence and invite discussion and argumentation. If less than 80% of classroom discussions of this screen offer the opportunity—the need—to discuss Zeno’s paradox, then the Friday Fave will eat its Desmos sunglasses.

Not only do we delay feedback on the correctness of students’ work, we use the moment of giving feedback to spur further conversation.

Give this activity a whirl with your algebra students and report back on how it goes.

Fellows’ Lounge for October 31

In this week’s prompt we asked the fellows give this activity a makeover, increasing its depth, demand, or delight, by adding just one screen.


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Though the makeover screens varied widely depending on lesson objective and course level, there were commonalities in how the fellows used Desmos to add value.

  • They connected representations.
  • They gave students opportunities to be right and wrong in different, interesting ways.
  • They created activities that are easy to start and difficult to finish.
  • They created objects that promote mathematical conversations between teachers and students.

(These are all elements in our activity building code.)

Connect representations.

Dan Anderson, Stephanie Blair, Sarah Blick Vandivort, Meg Craig, Nolan Doyle, Adam Poetzel, Julie Reulbach, Linda Saeta, and Suzanne von Oy all used a graph to help students connect the algebraic representation of functions to the graphical representations of functions. Directions on these screens asked students to represent various values of a given function. The way in which students would respond ranged from less formal representations such as dragging or sketching points to the more formal representation of plotting a point by typing its coordinates. Several of the fellows also made use of color and styling to help students interpret a graph or display understanding.

Give students opportunities to be right and wrong in different, interesting ways.

Dave Sabol and Jenn Vadnais included a table of values to help students reason about function operations and composition. In Jade White’s screen students can take a numerical or algebraic approach allowing them to get to the answer in a number of ways, creating an opportunity for rich class discussions.

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Create activities that are easy to start and difficult to finish.

Mark Alvaro and Dave Sabol added challenge screens to our original activity, making it easy to start and difficult to finish.

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Try your hand at Dave’s Marbleslides challenge here.

Create objects that promote mathematical conversations between teachers and students.

Serge Ballif, Nick Corley, Dan Henrikson, Paul Jorgens, Scott Miller, and Anna Scholl created screens that promote mathematical conversations between teachers and students by including problems designed to expose and confront naive conceptions that students may have. An example of this is Serge’s card sort, which gives students a chance to see both correct and incorrect uses of function notation.

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Check out all of our activity additions here.