Sub group dialect and slang is a much studied part of anthropology. Teenagers (in this case a sub-group) use specialised language all over the world. My anthropology lecturer was doing a study on high school boys in a private school and their specialised slang - I remember him saying (as it was a longitudinal study), that the slang changed very rapidly.
I can usually spot someone my age if they use the term ‘cool bananas’ because no teenager now would be caught dead saying this!
whoops, please ignore, trying to respond to a thread and had login issues!!