There is an interesting exhibit for kids about 'unpolite science' in Paris, at la cité des sciences et de l'industrie, it's called Crad'expo (crade in french means dirty). It is all about the making of boogers (dried or not), farts (wet or not), throwing up and so on. The idea is to explain those biological mechanisms, which is IMO a good point. I think this exhibit is inspired from something that has already been showed in the US or Canada, i don't remenber. Update: it's grossology tour.