How much is the right amount?
I'd encourage you to take the pulse of your friends and neighbors to see how much they're giving. You don't want your child to receive much more or much less than his or her peers. You could also resort to national averages, which start at about $1 a week in kindergarten and go up $1 for each year in school. But the best way to determine how much money you'll give your child each week is to decide what you expect that money to cover. Make a list, figure out how much those items cost and then present it—as a fait accompli—to your kids.
Use this easy tool to help you complete your list: