Classroom attendance script

I need a script that will help me keep attendance for a school. It would have tables for students, classes, discounts, days_attended. It would be able to email invoices for tuition to all students on a monthly basis. The admin would be able to ADD/EDIT/DELETE Teachers, Students, Classes, Discounts, and Days_Attended. I would like the Teachers to be able to sign in and provide attendance data for their class. (Who was scheduled for their class, and they check who was not in attendance) This attendance would then be used to calculate what the invoice is for that month for that student. The students who are signed up for class XYZ, would be on the attendance sheet for teacher of class XYZ. She would login, see her scheduled students, adn check the ones who were not there. The admin can ADD invoices for ALL, one, or a selected set of Students. The fee is in the Classes table. The Discounts are in the Discounts table and are applied to the Invoice for EACH STUDENT per the discount info for that student pulled from the Discount table.