My high school was very welcoming to Freshman, as long as we stayed off the Senior Lawn. That part of the school was strictly for seniors only, and was strictly enforced by the seniors. But that was just one grassy area of many. Everywhere else, no one actually cared what grade you were in, as long as you fit in with the social group. That was back in the mid 90s, so things like "Preppy" versus "Rocker" versus "Nerd", etc, were very rigidly defined.
Peep I was scared too, once I had spent about a month there I became friends with several of the seniors and got a lot more comfortable. It just takes time, in my experience everyone is scared going in
Dusk, I hated high school. I wanted to skip class if we were just watching movies, especially if it was for entertainment without educational value. Grapes Of Wrath? OK, that had educational value. Ace Ventura? Fun, but no educational value, and I'd rather watch the whole thing rather than just the first 45 minutes. So, I would slip out of the classroom right after attendance, and not return. I was bad.
I prefer how it was in college. A final exam on the last day of class and then DONE! Except I had one professor that gave me and a few other students the stink-eye for taking the final exam. When I handed mine in, she said, "Why did you even how up? Your score for this class is so high, you could have skipped this entirely and still gotten a passing grade. Now I'm obligated to grade this. This is extra work for me." Um... Because I cared about my GPA and an A is better for a strong GPA than a C. Ugh! That professor was the worst!