My brother

[Orangeflamingo]

I have a younger brother who is 12 years old. He is very quiet and reserved at school and outside but at home is very hyper and somewhat crazy. He will enter my room and stare and leave. And just come in to say hi for no reason. He is extremely secretive about his new phone and gets very weird when I want to take a look at his phone.

[Sandman2]

Doubt it.  ADHD has to exist in both places -school and home.  You can't just turn it off and on.  He probably is just glad to be at home and be more of himself after a long day.  I am guessing he is in 6th grade which puts him at the bottom of the school "pile".  That can be stressful.   Phone is understandable.  Might have a few things there he doesn't want to share.  Hope this helps.

[Orangeflamingo]

Is this ADHD??