I prefer the live action TV series, but the Sukeban Deka series is great. It’s about a high school girl who works as an undercover agent for a branch of the police that investigates crimes that take place at schools that regular cops aren’t allowed to investigate. Unfortunately, very little of the franchise has been officially released in a English. ADV released the OVA in the 90’s. The 2000’s movie reboot got a release too, but that was the worst version IMO.
I’m no expert on this, but in addition to the other factors people mentioned, I would say that people in Japan seem to pay a lot more attention to high school sports. The Koshien Stadium and the high school baseball tournaments name after it are very famous. I’m not even interested in sports, but I know about them and often notice friends talking about them online. I know absolutely nothing about the college baseball tournaments or where they’re held.