Mixed on this one. I think it's a good experience to teach your kids independence but you don't teach them to swim by hurling their asses into the ocean either.
By the time I was 10 I was cooking dinner for my brother, splitting firewood to keep the fire going (heat house) and was on my own from 7am to 9:30 pm.
We were expected to do dishes, help with laundry and house cleaning was all us.
I still remember my brother and I had to each hand cut 10 logs and split kindling daily to keep the supply up.
It was a great experience but a few years later we got into all sorts of trouble that could easily have been handled with more supervision.
I don't blame my parents for all that though. I was a crazy, adventurous little nut case.
Scott