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# Understanding Desmos: Sonification lessons

## Learn about talking graphing calculators, audio tracing and how to teach it with these activities!

As TSVIs, we are always looking for math tools, especially accessible digital math tools. General education students in math and STEM classes across the US are using Desmos, an advanced graphing calculator. Desmos is an accessible web application and a mobile application; it is often an embedded tool on the calculator portion of many high stakes assessments and is used on many year-end tests.

Yes, Desmos is accessible with a screen reader; but that does not mean that if your student is efficient with a screen reader that he/she automatically understands how to use Desmos’ audio tracing to complete graphing assignments. Like stand-along talking graphing calculators, Desmos uses sonification to represent the coordinate plane and graphing. Hmmm, sonification – this term keeps popping up! How does sonification and audio tracing actually work? This post will introduce you to how Desmos uses auditory tools!

## Terms

• Audio trace mode: Allows the student to explore a graph by sound rather than sight. It is used to discover how one or more curves are graphed on the screen. This is the term that Desmos uses specifically for audio graphs.
• Sonification: Sonification is the use of non-speech audio to convey information or perceptualize data. This can be a more generic term.

These two terms are often used interchangeably.

In the previous post, Desmos Audio Tracing: Introducing Sonified Graphs, Dr. Yue-ting Siu shares how she introduces audio graphing to her second grade student. I particularly like how she discusses all the “pre-work” lessons done with the student before hands-on listening to an audio graph with Desmos!

This 3-minute Accessibility Features in the Desmos Graphing Calculator video provides an overview of how Desmos audio graphing works with JAWS. Share this video with your student who is learning Desmos and with your student’s math teacher!

Want to dig deeper? Check out this video, Demos Online Graphing Calculator with JAWS: Create and Explore a Graph created by Campbell Rutherford, a high school student interested in Applied Mathematics and Dr. Besty Doane, a retired math professor. Campbell uses Desmos with JAWS and her Focus 40.

Note: As the videos indicate, it is important that your screen reader has the right features set for Desmos to work correctly. See the Screen Reader Setup on the Desmos website for details for your device, screen reader, braille display and browser.

## What does the sound mean?

Let’s review the Desmos graphing sounds that were introduced in these two videos:

• Pop: Where two lines intersect
• Static or “hush” sound: Graph is below the X axis
• Pitch: Indicates the location along the Y axis; the higher the sound, the higher on the Y axis
• Stereo Sound (left/right ear): Indicates the location along the X axis
• “Graph Paper” Announcement: Just like a screen reader will announce the type of a graph (bar chart, pie chart, scatter plot, etc.), the screen reader will announce “Graph Paper” for the graph on a grid.

## Desmos basic commands

Windows/Chrome OS command is listed first followed by the Mac command in parenthesis.

• Enable or Disable Audio Trace: Alt + T (Option + T)
• Hear graph: H (H)
• Summary: Alt + S (Option + S)
• Next point on grid: Right arrow (Right arrow)
• Previous Point on grid: Left arrow (Left arrow)
• Next Point of Interest: Tab (Tab) [POIs are coordinate points]
• Announce the number of POIs: P (P)

• Move to Origin: 0 (0)
• Adjust Playback Speed: Alt + 1 (Option + 1) [Playback speed options are 1 – 5 with 1 as the slowest and 5 the highest]
• Increase Volume: V (V)
• Decrease Volume: Shift + V (Shift + V)
• Describe the Graph Axes: Alt + G (Option + G)
• First Point: U (U)
• Last Point: N (N)
• Speak X Coordinate: X (X)
• Speak Y Coordinate: Y (Y)
• Speak Color: C (C)
• Move to Next Curve: Alt + Down arrow (Option + Down arrow)
• Move to Previous Curve: Alt + Up arrow (Option + Up arrow)

## Lesson

Now that you (the educator) have an idea about how audio graphing and your student is familiar with tactile x-y graphs, you are ready for a transition lesson that pairs auditory and tactile graphs.

• Listen to the sound clip first.
• Ask your student what the audio sound represents (describe it using words)
• Ask your student to draw the line/curve using the Sensational Blackboard or Draftsman. *
• Use your teacher-created tactile graphic, compare your student’s drawing to the provided drawing. (Desmos graphs can be sent to an embosser or you can create your own tactile graph.)
• Listen to the sound clip again, while having your student trace the tactile drawing.

* Note: Your student needs to be able to quickly create simple drawings using simple tools, such as the Sensational Blackboard or Draftsman. Do NOT skip this step! I strongly recommend that every braille student carry a Sensational Blackboard in his/her school backpack!

Here are some samples that you can use. If possible, also use samples of lines/curves that the student’s class is using!

y = x audio clip

The pitch increases as it moves from left to right, indicating a positive slope. There is static at the beginning as the line is starts below the X axis (until the line passes through the Origin).

y = -x audio clip

The pitch decreases as it moves from left to right, indicated a negative slope. There is static at the end as the line drops below the X axis.

These audio clips and images are from the Desmos Accessibility page; scroll to the bottom of the page to find the Audio Trace Examples. Additional audio examples are available, and all examples have a link which opens to that specific graph in Desmos.

When your student is ready for hands-on exploration of Desmos, open the graph link (or type in the equation) in Desmos and have your student practice the Basic Desmos Commands above.

## Resource

Exploring Math with Desmos: Getting Started (includes a video tutorial of Desmos in Braille Mode)