Part time work on a student visa

I am enrolled in a chinese school in shanghai on a student visa. I was recently offered a parttime tutoring job with a private language school. I have not accepted the job yet but the employer has not discussed with me any legal implications regarding working as a student in china. In your article you mention that "with permission" from the school, I may be able to seek work. Can you elaborate? Would I be in any legal trouble if I started working on a student visa?