Ha- they've always been out of touch with youth culture. I remember back in the day the crazy dramas about kids being in a line to watch a "R" movie or smoking cigarettes. Meanwhile in my school teens were doing acid/ecstasy and smoking pot.
I'd say that type of letter is pretty unlikely unless you were living in some backwards country where there's no access to civilization (aka internet). Now kids just send snapchat messages to each other I would be skeptical of any letters with complete sentences from teens...lol. That's completely made up.