Count number of related table to another related table

I have tables for Events, Contacts, and Schools. (There are about 12 other tables but not relevant to this)

The Events are related to the Contacts (multi-select)
The Contacts are related to the Schools (more than one student can be associated with the same school.

My goal is a view or report that lists the event and the NUMBER of students from each school that attended the event.
So it would show:
Event Name, Number of students associated with School #1, Number of Students associated with School 2, etc.

I tried using a rollup field but am lost on the proper setup.
Any help with as many specifics as possible would be appreciated.