Sensory/Science bottles -- Science for kids, why yes! 13 bottles with different science principles (density, static electricity, magnetic, sink or float). Made from old water bottles and with most things found around the house.
Balloon Rockets - I've done this in several science camps I've conducted. Kids have fun with it. But, when the balloon deflates it may fall off the straw because it's surface area changes - another good thing to show and explain to kids.
The Penny Experiment - a fun easy science experiment for kids. This would be a fun science exploration for President's Day. Kids can determine what else they would use on the pennies and compare results