Decide what your child responds to. The rewards must have meaning for him if you want him to study hard, get good grades and display good conduct in class.
Choose small, inexpensive things you can keep hidden as tangible rewards. Pick things that further her education in a fun way like a book, game or puzzle. Items that help him improve coordination or get physical exercise are also good choices.
Use intangible rewards as often as you can. A trip to the park or museum, a visit to a friend or creative play expands her mind while providing a break from the learning routine.
Create choices for rewards. This boosts your child's self-esteem because not only does he get a reward for getting an A on his math test, he gets to decide what it is. Switch between tangible and intangible choices so she doesn't always pick the game over the museum visit.
Give encouragement with every reward to emphasize your child is getting it for good behavior. Make sure that overshadows the item or benefits they're getting.
Use stickers to encourage good school conduct. Buy a notebook and list all your child's school subjects. Track grades on tests, quizzes and report cards and let him choose which sticker he gets in the notebook as a reward.
Discuss the rationale behind intangible rewards where appropriate. For instance, more friends is a reward for good conduct in class. More interesting material in advanced subjects is a reward for good grades.