Coding Projector Games

#1

I am new here and am not entirely certain where the best place to post this question so hopefully this works. I am a teacher and would like to teach my students how to program games that use a data projector to display games on the floor that students can then interact with. I have seen this done at places like science centres and there are some software packages that can be purchased, but as I am the person who has to pay for all of this a free option would be better. I believe OpenGL can support this, but cannot find anything specific; it may be because not many people are doing this, or I am way off base, or I am just using the wrong search terms.
If anyone can help provide any direction it would be really appreciated.