Student Worries...

There is a student in my class...he sort of breaks my heart. He doesn't do his work, generally talks back when spoken to and gets some of the lowest grades in the class. However, he recognizes the fact that he does these things and says it's because he isn't intelligent. He speaks intelligently. My mentor teacher seems to have no interest in helping him. How do you motivate someone when you know they are capable of better things?