Does this count as a necro here?
Anyway, I'm kinda upset that no one's mentioned depression or anxiety as a possible cause of irritability. I remember last school year (age 15-16), I called my father a couple of times out of desperation and a need for help--I thought my heart was beating wrong or I was hearing voices--and to express my utter apathy toward school, and it always ended in arguments where I threw the phone across the room. Plus, I get sensory overload or something especially when I've been through a lot of stress and I can't be polite because I'm barely not spazing out--this Christmas, I was opening gifts at my father's house and by the time I got to a couple pairs of pajamas, I couldn't express gratitude because the texture freaked me out and the best I could do was put them out of sight for a while and scrape my fingertips on teeth while speaking with my whole body rigid and expressive with energy.
I've learned to recover pretty quickly from being overwhelmed by things, and the overload has lessened with age, but I think that's definitely a factor in kids seeming to have an attitude. Letting your kid know they can and should apologize or make up for outbursts or periods when they had to cocoon for a while and that that's more important than not being rude in the first place is a good idea to keep serious fractures from developing in the relationship.
