My daughter is 12 ( in 7th grade ) and gets $25,00 per week. I know it is a good amount of money, but she was constantly asking for things and we found this an easier option. She is learning to handle money and how she spends it is her choice.
My kids receive $1.00 per chore that is completed without being told. They each have the opportunity to earn up to $14.00 a week ... of course they usually only get $5.00 because they somehow NEVER remember what needs to be done.