Calm Down Jar. It is really easy to make. The goal is that when they are feeling out of control, they shake the jar, then sit and watch the glitter settle in the water. When the glitter settles, they can get up. This one is a really great technique to use in lieu of timeout.
Mind Jar -- meditation tool for all ages: "when stressed, overwhelmed, or upset, imagine the glitter as your thoughts/emotions. when you shake the jar, imagine your head full of whirling thoughts/emotions. then watch as they slowly settle together, and you calm down."