Mad Science Camp: Discrepant Events

I love discrepant events.  What are they?  Usually, discrepant events are demos that make kids think.  I used to set out discrepant toys in my classroom.  My favorite is the Poly Density Kit.  Even the kids who put the kit together have difficulty explaining the phenomena.  (Spoiler is here.). Another discrepant event is the Shrinking Coin Bank.   (Here is a micro-bank opened to show the mirrors.). Have you tried the Disappearing Beaker?  (The link has the underlying optical science.  Basically, light canola oil has the same index of refraction as the Pyrex beaker.)  Here are nine pages of discrepant events for science.  You’re welcome.