Agreed university is much harder though.
I was an air force brat, and so attended many diverse public schools.
I took 2 years of honors physics in high school. College freshman physics blew through that in 2 weeks. And then I was in deep doo-doo.
I am eternally grateful to Prof Ricardo Gomez, who kindly took the time to coach me one on one. I never thanked him for that, one of my many regrets.
When I went to college, it was definitely tougher, but I was able to pass the freshman physics and multi variable calculus courses first time around, without significant tutoring.