I use mystery science in my classroom this year and my kids LOVE it! Free open-and-go lessons for elementary teachers that inspire kids to love science. Meets Common Core and Next Generation Science Standards (NGSS).
Ed Dancing raisins activities. Lots of fun experiments. I have done this experiment, and seen the entire class become silent out of curiosity. It is a great engagement piece for a lesson, and it can be hands on if you ask for volunteers!
Fifth Grade Physical Science Activities: Molecule Madness: A Water Experiment (this is also why you add dish soap to vinegar/water fruit fly traps-- it eliminates the surface tension on top so they sink and drown. I know, so morbid!