TJ's school teaches the kids to be polite, but also to be assertive. Most three year olds don't seem to have a problem with letting others know how they feel.
The school does not encourage inappropriate behavior and will say to the kids, "No, thank you, that's not how we treat our friends" or whatever the appropriate response to the situation is.
Well, TJ has taken to using this term but has added his own little spin to it. Whenever someone does something he doesn't like, he will say very meanly, "no THANK YOU!" with an emphasis on the "thank you" - he'll say that part very loudly. Sometimes I try to give him a kiss and he may not want a kiss right then, again with the mean "No THANK YOU!" - I hate to say it but it makes me laugh every time.
I try to hide it from him because once he knows what works to get my attention, he definitely will use that trick again. Case in point, funny faces at the dinner table. "Look at this face, Mom." Or his new favorite song and the dance he does to the classic "Shake what your momma gave ya." I told him that one was only for home. Politely, though. Maybe if he does it out in public, I'll try his old standby - "No THANK YOU!"