Another fairly simple way to make money for kids is by washing cars. Have your kid pass out fliers or stake out in a community parking lot, with signs and supplies and flag down people that need their cars washed. According to the Kids Money website, kids between ages 10 and 15 can charge $5 per car. For continued business, have your child stake out in the same place each week -- Saturdays are best -- so people always know where to find your child.
