Most back-to-school advice works for kids who like school. What about kids who don't like school? Not liking school doesn't mean a child is going to fail at life. Traditional classrooms and teaching styles are not for everyone.
I first heard about 'hikikomori' on a visit to Japan 25 years ago. It was a new term then, used to describe severe and prolonged school refusal in teenagers, sometimes evolving into complete social withdrawal.
"I don't want to go to school" seldom means just that. It is usually the tip of an iceberg. There is either a need that is not being met or a cry for help about something. It is your job as parent to play sleuth and figure it what is really going on.