Desmos.com is my number one use of technology in my classroom. My students and I use it to create lines, analyze data, and solve problems. The interface is simple and user-friendly.
Here's how Desmos describes their product, "At Desmos, we imagine a world of universal math literacy, where no student thinks that math is too hard or too dull to pursue. We believe the key is learning by doing. When learning becomes a journey of exploration and discovery, anyone can understand – and enjoy! – math.To achieve this vision, we’ve started by building the next generation of the graphing calculator. Using our powerful and blazingly-fast math engine, the calculator can instantly plot any equation, from lines and parabolas up through derivatives and Fourier series. Data tables open up a world of curve-fitting and modeling. Sliders make it a breeze to demonstrate function transformations. As browser-based html5 technology, the graphing calculator works on any computer or tablet without requiring any downloads. It's intuitive, beautiful math. And best of all: it's completely free."
The best way to start learning about Desmos is to launch the calculator and just start playing with it. Make sure that you check out the Just Add Sliders, Tables of Data, and Regressions tutorials on the main page. These are some of the coolest features of Desmos.
Desmos sliders have transformed my teaching of linear functions. Sliders have helped my students understand how manipulating the slope and y-intercept of an equation changes the graph of the line. What are sliders? Check it out:
Once you have graphed a line in Desmos, you can click on the line to find ordered pairs that lie on the line. If you have two lines graphed, you can click on their point of intersection to find the solution. Adjusting the window is as easy as zooming in or zooming out like you would do in Google Maps.
I also love the artwork on Desmos. Last year, almost half of my 8th grade honors students had used Desmos to figure out how to graph circles so that they could make their graphing art more interesting. One student was even graphing sine waves and animating them with sliders. He figured out how to do this in his spare time at home. In class, I never taught any graphing beyond linear functions. On their own, my students used the art examples on Desmos to learn so much more than that! Students can create an account so that they can log in and save their graphs.
If your students are going to be creating art in Desmos, they will want to know how to 'end their lines' by creating domain and range restrictions. (Did you catch my use of the phrase 'want to know' in that last sentence? I'm not kidding. Your students will be begging you to teach them more math once the magic of Desmos gets under their skin.) Here's a quick tutorial on how to do create domain and range restrictions in Desmos:
I'd love to hear your thoughts after you spend some time playing with Desmos.com. Have you used it before? Do you use Desmos or a similar graphing technology in your classroom? How do you incorporate graphing technology into your classroom?
About the author: MaryAnn Moore (@missnarymm) teaches 8th grade math in Davis School District. She coordinates the UCTM teacher blog and is also a regular contributor to the UCTM teacher blog. Please email her at firstname.lastname@example.org if you are a Utah teacher interested in contributing to this blog.