Universe in a bottle would be fun to use for kids: need a mason jar, glow n the dark paint, fanned small paint brush and lid for jar. Dip brush into the paint. Tap the brush on the edge of the jar letting the paint splatter inside the jar. Continue until you can see paint splattered all inside jar. Set in sunlight all day to soak up the light for that night's magic.
PBIS calming down idea--squishy marble maze. Gallon ziplock bag, duct tape, dish liquid, and a marble. Could always add glitter :o) Great directions and photos. I think this would also work as a class reward option (if I make enough). :o)