Desmos has been something that I have wanted to explore for several years. I have had good intentions to put aside some time and play with it. That time has never materialized, though, for a number of reasons. When I looked over the schedule for NCTM’s Annual Conference last spring and saw Ivan Chang’s (@drivancheng) session *How to Desmoify Your Math Lesson to Promote a Growth Mindset, * I made sure to build it into my schedule.

The session was really well done. The presenters built in time to play within the software and gave great guidance on building a lesson for Desmos. They talked through the idea of starting the plan for the lesson on paper, making it dynamic, and doing multiple iterations. They talked through good pedagogy (building the lesson to start with discovery and sense-making, moving on to solidify understanding, and then formalizing the concept). They demonstrated how student work can be projected in real time and how it can be anonymized to protect student privacy and ensure that there is academic safety.

When I returned home, I decided that I want to begin by using some Desmos lessons that have already been curated. I picked three lessons that pertain to CCSS standards relevant to my course from their “favorites” list to try.

- Battle Boats – This is a lesson on graphing on the coordinate plane. Usually, I have students play Battleship when I teach this concept, so this is an extension of that idea that uses Desmos. I think it will be an easy entry point for our first foray into Desmos.
- Inequalities on the Number Line – This is a great lesson that enables students to construct an understanding of how/why the graph of an inequality comes about as they plot points on the number line that fulfill the inequality and then see how the graphs change when all the points their classmates also plotted are added to the number line. I really like the way that it builds the idea of a ray as the solution set and the way that it builds the idea of a closed or open circle.
- Graphing Stories – This is a nice lesson matching graphs to stories. It is similar in concept to a lesson that I already teach. After looking at this lesson, I decided to use this as a model of sorts for creating my own first Desmos lesson. I like the idea that if it crashes and burns, there is a back up plan for second period. Thus far, I have built the introduction to the lesson and a card sort activity. I still need to build a closing formative assessment.

In building my first Desmos lesson, I learned how to build graphs with complicated step functions using their software in order to get the graphs that I wanted. I also learned how to build a card sort in Desmos. Given that, even if I decide the lesson isn’t as good as the existing lesson in the Desmos “favorites” and that it would be better to use their lesson rather than my own, I feel like the time was well-spent.