One of my favorite interactives is part of the "Inventions at Play" series from the Smithsonian Partner site. It is "Tinker Ball!" I have used this at the Smithsonian several years ago and at the American Library Association Convention last year. It works for young and old. Most of our students have a BIG problem with "problem solving," and this is something everyone gets hooked on.
Exploratory play is about asking questions: “What happens when I do this?” “What if I did it this way?” Experimenting with materials and pushing their limits encourages us to consider a wide range of possibilities when problem-solving. Playing around with objects and ideas helps us see that there may be more than one solution.