My schools assistant principal went through my iPhone notifications infront of me while I was getting it back, is that legal?

I got my phone taken away during bio and after school (I'm a freshmen btw) when I went to go get it, everything seemed normal at first but as he was gonna give it back he turned on my phone and scrolled through my notifications, and even started questioning me on what he saw on my own phone? I was wondering if this is even legal? Cause technically he didn't unlock it but he saw like all of my notifications and even went as far as to question me on it? He also gave me a lecture too on what he saw…

Schoolteachers and principles etc. Have pretty much the same legal authority over you as your parents.
The legal term is "In loco parentis".

They had the right to search your property, your locker - and your room, if you live in a college / university dorm.

They can't use things they find in criminal matters, but they can suspend or expel you if you break rules.

Can you leave the phone at home and try to learn something pumpkin head?

It is legal,
and you really should learn more about the rules at your school.

Now you know not to have anything show on the lock screen, that is if you don't want others to see it.

The difference between me and you, you got caught and the phone was taken from you. That would never have happened to me.

If the rule is done take your phone out in class, don't take your phone out in class. If you need to go out of the room, get a pass to the bathroom, check your phone there or on the way. Or check the phone on the way to class.

The answer is yes. Remember you brought the whole thing onto yourself by taking your phone to school. The administration was right to take it from you. It's about time you started following your school's rules about cell phones on campus. Consider leaving it at home next time.