We're learning conic sections in precalculus, and so far it's just been 2 days on each (circles, ellipses, parabolas, hyperbolas). We've covered the first 3. That was the bulk of how I was going to present it: create the conics with either paper folding or strings and pencils, and then get to the equation and then "work them to death". THEN. I kept reading about these elliptical pool tables where if a ball is at one focus, then any where you hit it, it will bounce off the wall and pass through the other focus. I think that's the coolest thing. I mentioned it to my 3 classes, and they got excited, so I think we're going to try and make one for each class to test this thing out. I told them that then we could be pool sharks and place bets with nonsuspecting non-mathies.
My latest idea is a thick wood piece left over from shelves, the inside part hollowed out in an ellipse shape, and then the thickness can be the "walls" of the table and we can use a marble as a pool ball. I'm so curious to see if this will work out.
On a funny side note. When I started the conic sections, I mentioned the properties of a parabola where if you put a microphone at the focus or a light bulb at the focus it has special "powers" because everthing "bounces" through there. Then on Friday one of my students had mentioned that he was at an electronics store and he saw this music contraption where it had a dome (I guess in the shape of a paraboloid) and a person would be the only one to hear the music. He said he was then thinking about what we talked about in class, and he joked that he called people over and gave them a lesson on parabolas.