GeoGebra Accessibility
- Author:
- GeoGebra Team German
GeoGebra provides accessibility features for both our GeoGebra Math Apps and Classroom Activities. In this video, we demonstrate the use of a screen reader in a typical classroom Activity exploring the circumference.
Navigation
The GeoGebra Math Apps include a “tab order”. Users can easily tab through either user interface elements (menu buttons) or math objects (ie Points, Lines etc) in a classroom activity. Each GeoGebra menu item can be opened with the < Enter > key and has its own tab order integrated. You can leave the Settings menu with < Esc >. The Main Menu can be left by tabbing through. In each menu you can navigate with < Tab > and also with the arrow keys < Up > and < Down >.
Useful keyboard shortcuts are as follows:
- With < Tab > you can cycle around user interface elements and math objects. In GeoGebra Classic the tab order can be changed by dragging the objects in the Construction Protocol.
- If a slider or a point is selected, you can use the arrow keys < Left >, < Right >, < Up > and < Down > to move them.
- With < Space > you can trigger a button, toggle a checkbox, open/close a drop-down menu and start/stop a slider animation.
- < Plus > and < Minus > keys move a point on an object (for example a Point on a Line or Circle).
- < Enter > is used for editing objects.
Designing Accessible Applets and Activities
To make GeoGebra activities accessible you will need to consider the following design principles:
Fontsize
Select a large Font Size in Settings → Global before starting your GeoGebra construction. You can use the keyboard shortcut 2 to make all fonts bigger and all lines thicker. 3 changes the default for all new objects to black and unfilled.
Color
Use high contrast colours, such as dark colors on a white background. Lines should be thick. Avoid using Red, Green and Yellow as they have poor contrast when used with a white background. Whereas Blue, Dark Green and Dark Red all provide excellent contrast.
Style
Use different line styles (for example, dashed) to distinguish objects instead of simply colour variations to provide non-colour dependant contrasting objects. Similarly different Point Styles help distinguish one type of point from another.
Sliders
When using sliders, make sure that they are as long as possible, supporting a wider range of fine motor skills. Change the Slider length in Settings → Slider → Line Style. Consider adding Buttons for “decrement” (Script:
SetValue[a,a-1] ) and “increment” (Script: SetValue[a,a+1] ) at each end of the slider.
Selection of Objects
As mentioned before it is possible to cycle around all math objects in GeoGebra. If you want to exclude any math object, simply uncheck “Selection allowed” in Settings → Advanced. You can also use the shortcut D to toggle this for all objects except free Points, Sliders, Checkboxes, and Dropdown-Menus.Screen Readers
GeoGebra Math Apps and Activities are accessible by screen readers (for example NVDA, JAWS and VoiceOver). Mathematical objects in Activities (such as Points, Buttons or Sliders) are automatically read by the screen reader as are GeoGebra Math Apps menus and keyboards.
When starting the GeoGebra Graphing Calculator the focus lies in the Algebra Input. The screen reader provides the message “Enter your equation or expression here”, prompting you to start using the calculator features.
You can also attach text and define math objects when creating a new GeoGebra activity, providing the opportunity for further and extended descriptive texts read by the screen reader.
- To add a Caption for each object go to Settings → Basic and this will be read out instead of the default description.
- To create a text describing the whole view, create a Text called either “
altText”, “altText2” or “altText3D”. It will then be attached to the Graphics View, Graphics View 2 or Graphics View 3D respectively.
GeoGebra and Accessibility Standards (WCAG 2.1)
GeoGebra’s Math Apps and Activities support the Web Content Accessibility Guidelines (WCAG) 2.1 at level AA.
For further information about accessibility and how to ensure your GeoGebra teaching and learning workflow complies with accessibility standards contact office@geogebra.org.
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