It would be helpful to have the parents to be able to access the student account as a payor.  The student would go into their account and designate their parent as being able to pay on the account and any other permissions that want to give, such as grades, discipline, or schedules.  I would think this would somehow tie into their FERPA form.  Once the student has authorized a person they would get an email invitation to have them set up an account for viewing items and making payments.