I used to scold my son because he is not studying his lessons at home . Instead he keeps on playing around doing other stuff. What would be the great motivation to help him encourage to study his lessons ?

How old is your son? You also might want to consider his age. If he's in pre-school, most likely he is still adjusting to his day to day activities. You can try reward system instead of scolding him. You can reward him with his favorite food, toy or a play at his favorite play house if he studies well. You assess what would motivate him to focus on his lessons.