Idea-Quiet Critters - when you decide it's important for students to be quiet, pass out the quiet critters. Take them away from students who talk. At the end of the activity anyone who still has a quiet critter gets a prize, point, whatever you use.
SCIENCE FOR CHILDREN-Having already done this, it was a great addition for sand and sensory for even toddlers. Developmentally appropriate for children of all ages depending on what is added. Will abs (How To Make Slime With Flour)