This isn't my school but the school a few streets away from ours, year sevens HAVE to wear a clip-on tie. One person got an after school detention for not wearing one.
In our school, there's an upper school and a lower school and when I was in lower school, my mate had fitness club in upper school and on his way back to lower school some guy would stop him and if he said he's year 8 he said "Ha, that's what they all say"
Basically, unless you have a lesson in upper school you're not allowed there and vice versa.