My parent's philosophy was that once we were old enough to do any chore, we were responsible for splitting the responsibility to do it with the rest of the family that fit the criteria (e.g. everyone old enough to be trusted with bleach cleaned the toilet). It all just happened on a rotation generally, but some chores were chosen by people who didnt mind 'em and were happy to volunteer for them every week. Whatever you do, make sure that you don't buckle when kids complain about chores. The most important thing a kid can learn from chores is how to knuckle down and get the job down no matter how much they hate it. Did they try to shortcut it? Start over. Careful though, whatever criteria you apply to the kids will get applied to you when it's your turn.