I'm teaching Blender to my high school students this year and it is a main piece of our worldbuilding course. One of my students is visually impaired (and hearing impaired) and I'm wondering if there are any accessibility features or add-ons for the program. Right now, it seems like there's nothing available, which surprises me. I searched Google and all I've found are a couple of posts where other people are inquiring about this. Can anyone point me in a useful direction for this sort of topic. My student is willing to work hard and she has enough vision to navigate on a computer, but she also emphasized that her vision "fluctuates" and Blender's complexity and small text makes it very tough. Any assistance or insight would be greatly appreciated. Thanks. best, Kas P.S.: I am new to this site, so please forgive me if I've missed something.
I looked around for some resources for disability features in Blender and came up against some similar problems you did. Looking through this forum thread came up with some interesting routes to make your students Blender experience a little bit easier. Notably this Print-Friendly Theme that overhauls Blenders UI and should hopefully make it a bit easier to use.
There's also a lot of settings you can change inside of Blender that can make it a lot easier to use and more focused on hotkeys and typing which might be easier than navigating with the mouse. For one, a big setting I always like to change is making the Spacebar set to open a search menu that lets you have super easy access to a lot of features that are usually pretty hard to find or remember. To activate it, go to the top left of Blender, click Edit, and from the drop down select Preferences at the bottom. From the Blender Preferences menu, you'll want to go to the section named Keymap, and from the preferences, change Spacebar to Search. Now whenever you need something, you can press Spacebar, type a part of the function you need, and then let autocomplete show you a bunch of options. This feature does replace having Spacebar as the play button for the animation timeline though, just keep in mind that Shift+Spacebar will work for that instead.
Another very handy setting to change would be under Interface, it's the setting called Resolution Scale. By increasing it you can make the icons a bit easier to read, and it'll increase the size of the text as well. There's even an option to change the font to something your student prefers.
You can change the colors of pretty much every single UI element in Blender with the Themes section of the preferences menu, and its where you can also install the previously mentioned Print-Friendly Theme. Hopefully changing the color scheme will make it easier.
I'm afraid I wasn't able to find any way to use a screen reader to make navigating the UI easier through audio, I really hope they add options for that in the future, as it's a real shame there isn't a framework for it already.
As an addendum to @NascentSpace's answer, note that you can set the resolution preposterously high (e.g., 3.0 or all the way up to 4.0) and -- while you're at it -- set the line width to "Thick", so grid lines and active object outlines are easier to see:
In the default workspace (the "Layout" workspace), resolutions this high typically make all of the areas except the 3D Viewport nearly unusable, BUT if you hover the mouse cursor over an area (e.g., the Properties editor) and hit CtrlSpace, it'll toggle that area in and out of fullscreen mode, like so:
Your student may find it useful to use the default "Layout" workspace at very high resolution as a kind of spatial main menu, jumping into areas like the Outliner or Properties with CtrlSpace, taking advantage of the full screen display as she moves between them. There's also the alternative fullscreen toggle CtrlAltSpace which fullscreens an area without any associated menus (technically, it fullscreens the "main region" of an "editor" within an "area"). This can be useful for distraction-free zooming of the 3D Viewport panel in particular.
Alternatively, if she reconfigures her workspace into a single big area, there are hot keys for switching the area between all those different editors: ShiftF5 for 3D Viewport, ShiftF9 for Outliner, ShiftF7 for Properties, etc.
At high resolutions, any component that gets cut off is scrollable, and that includes menus, whether horizontal or vertical. You can scroll them by either middle-click dragging, or by using the mouse wheel when the cursor is within the menu. Again, the mouse wheel works whether the menu is vertical (like the tools on the left of the 3D viewport) or horizontal (like a truncated menu bar at the top). There are more obscure controls available as well. In the Properties editor, for example, Ctrl-middle-click dragging will zoom the properties display itself in and out.
Also for the 3D Viewport, she should learn the T and N hotkeys to quickly toggle the toolbar and sidebar on and off, as they take up a lot of room at high resolutions. She can also disable the "Navigate" gizmo (either by toggling all gizmos off with Ctrl` or by unchecking "Navigate" in the "Show Gizmos" pulldown). This gizmo takes up a lot of screen real estate, and all its important functionality is easier to access with numpad hotkeys.
If she finds the grid floor distracting in perspective view, that can be disabled in the "Show Overlays" pulldown:
With the 3D Viewport fullscreened and most of the distractions removed (everything above plus disabling "Tool Settings" in the "View" menu), you can get a pretty clean 3D Viewport display:
If she prefers dark text on a white background, she can switch from the "Blender Dark" to the "Blender Light" preset theme in "Preferences -> Themes". Those are the only two built-in themes, unfortunately. Finding alternatives can be a little difficult, as themes tend to be pretty version-dependent, and they aren't always kept up to date.
Finally, you might want to take some time to review the User Interface section of the Blender manual, especially the "Window System" section. No human being can keep track of all the UI controls Blender offers, so I guarantee you'll find some tricks in there that your student will find useful.
Even more finally, note that everything in the "Preferences" menu gets saved automatically. Changes to the UI layout won't, but you can work with your student to configure a good starting layout with the venerable default cube and then use "File -> Defaults -> Save Startup File" to save that whole layout as her default "new file" layout. (Saving the desired default as a normal ".blend" file is helpful, too, so you don't accidentally overwrite your desired startup file, and so you can try out a few different alternative defaults.)