Straw Boats: Engineering Challenge Project ~ Great STEM Activity!
Make your Science Pop with Pop Rocks! This is a great example like Mrs. Patrick showed with inflating balloons. It is a similar experiment to the beaker, baking soda, and vinegar experiment. Kids love popping candy!
What does light shine through? http://whattheteacherwants.blogspot.com/2011/02/science-experiments-for-elementary.html
Some simple science experiments (on light) that the kids can do by themselves...station style. Very simple, yet the kids are working through the process to help get them ready for science fair season.