I hope people haven’t already done these, but here it goes:

JW- just wondering. An excuse to actually telling them why you wanted to know something.
Ex: “Why did you ask me who I liked?”
“Jw.”

Nothing- When most teenagers say that, it usually means their really is something. They either trying to tell you “leave me alone I don’t want to talk about it” or they want you to become curious and ask more questions. Usually the first reason applies.
Ex: “What is wrong? It looks like your crying.”
“Nothing…”

BBFL - best friends for life. It always gave me some sort of curse when I told someone that…
Ex: “Bye BBFL !”

Call/txt- It really means they want you to call or text message them instead of them calling you. They don’t just put it on their away message for nothing.
Ex: around the house, call/txt

...- either trying to be sarcastic or funny.
Ex: “Thanks a lot…”