That would be hard to source / use, as It's a bit dated. But the technic behind it could be replicated. It uses IR LED on the bezel, around a glass. With total internal reflection the light only shows up where you touch the glass. Then film that with a camera. The advantage to my method, you don't get interference of objects hovering above the screen. But getting the camera & display behind the screen, could be hard.

For me, when I said giant I meant a 8 by 40 foot wall projector that you could walk in front of and have the fluids trail off your silhouette

https://vimeo.com/27500054

https://www.youtube.com/watch?v=kfF3o2kLg0w

it's not the exact science museum experience mentioned, but a quick Google search for "sand table video augment" pulled up a few, and this was the first one I found: https://share.google/89A6x4yfaw5a4hOuh

When the first Xbox were getting long in the tooth, I believe people were repurposing the motion tracking bar as the mechanism to measure the topography of the sand table. That, coupled with a video projector mounted over the top of the sand table provides the additional colors and elevation lines. (And of course a bit of cool software to process and produce the image.)

I've seen the sand table installation before, pretty cool. I was interested in how they did the fluid in particular. Thanks anyway.