I'm not sure about paying kids for grades. Somehow it almost robs a child of doing something for themselves because it feels good. Paying them takes away the personal motivation. I guess I could see paying a child that really the extra encouragement or incentive. Perhaps paying a child after they've past the point of internal motivation. I didn't get any money for my grades until I was a junior or senior. It wasn't a certain amount or anything. I remember that all my grades were above a 96 and my dad gave me $20.