We use these jars the same way a teacher would in a classroom. Each jar starts out half-way full. When the kids are cooperating well together, we pour some beads from the sad face jar into the happy face jar. And, of course, when the kids are fighting or speaking inappropriately to one another, we pour some beads from the happy face jar into the sad face jar. I like that the kids have to work together to be rewarded!
You should hear the screams of joy (I can deal with that kind of screaming) when that happy face jar gets filled up! Does a mommy's heart good!