This happened all the time in my last school..
I was only there for freshman year, but at the time I was about six foot, and I had several friends (in the same grade) the same size, and some much bigger than I am. So when jerks on my bus openly talked bad about freshman, I usually just gave a little laugh to myself. His exact words (after pushing a smaller friend of mine around) were "freshman are like peeps, there are many but they're all marshmellows." That was his attempt at a witty insult, but he's probably 5'8. So I thought it was particularly funny, since I knew six+ personal friends much bigger than him. But other than size discrimination, that school had a bad problem with treating freshman like small children and just being mean to them. I was pretty glad to only be there for a year. :/