Answer:
This is a rather simple prompt, so I'll make my answer as short as possible:
My exhibit would be about travelling through time, because it would be interesting if you posted fake copies of Einstein's Principles, to make the exhibit more realistic looking as possible, and put in theories of wormholes, and the 'bending of time'. It could be a roller-coaster ride, and that would make it more attractive, in my opinion, of course. Hope this helps!