1. Usually schools only require girls to tie up their hair (ponytail, braids etc) with school-colour ribbons if hair is longer than shoulder-length. No need to cut.
2. I think most schools in HK do not allow students to RUN even in field / playground, because students might fall ==> parents complain ==> threaten to sue the school.
I don't like this rule either, but understand that the schools just want to avoid trouble / disputes with parents over this item.