When my kids were little they would constantly fight over who got to sit in the back seat of the van. Tired of trying to remember who sat where last and how many times, etc., I devised a simple rule: If today's date was an odd number, my oldest got to have the back seat, and if it was an even number, my youngest did. They never had a conflict about this again. I applied this rule to other things as well- mixing it up since there are more odd than even days. I know this only works with two kids, but hope the principle will inspire other ideas. Less fighting = happy mom!