Teaching visual tools for visually impaired students?
There are physical devices that permit the blind to feel three dimensional graphs. Do a search for something like &quot;haptic graphing device for visually impaired&quot; to see some of the possibilities. They aren't cheap, of course. One of the most interesting, I think, is one designed at Stanford University.
A simpler Braille printer might be adapted to make 2-D graphs, but may not work for 3-D.
Three Dimensional printers are a possibility provided that you have enough preparation time for creation of the models. They tend to be rather slow.
There are also haptic feedback gloves that might be adapted.