Is it legal for a school to deny waiver of days of absence because the diagnosis of the student/patient was not written on the slip?

I need to know where to look at the actual hipaa rule concerning this.

any help would be greatly appreciated. thank you in advance.

Am I misunderstanding your question? It sounds to me that a school is not allowing an excused absence due to illness, is this correct? If it is, how does HIPAA apply to this?