Every child needs an outlet, yet he still needs structure and rules at home as well as in school. So what is different in school than in the home that he feels he can be disruptive and wild at home. Are the parents not consistent? Do they not follow through with consequences and rewards? Is there something in the home environment ticking or setting him off that does not exist in school?
There are a lot of variables that have to be investigated to actually know for sure what is going on.