The first thing to do is to talk with your son. Ask him for reason of school avoidance. He might give you a valuable insight and direct your response. Perhaps somebody is bullying him or he has academic problems. How is he doing emotionally? Is he depressed, overly anxious, moody? If so, you might want to talk with a pediatric psychologist.
madam u should encourage him properly and u should understand him to value of education and give examples to him about education. u should create intrest with games and educational activites for him.in this way he will be ready to go for school.