This guy must never have heard about AP classes where large summer assignments are given out before the class ever starts. This is the norm in such classes, and it keeps a student's mind sharp over the lazy days of summer.
This dad is an idiot.
I did not have such assignments in my AP courses (U.S. govt. and American history).
I got a 4 and a 5 on the exam, respectively.
Summer homework is NOT necessary. I simply will not subject my students to it.