Does a 14 year old need an ID to travel on a domestic flight?

[sallyaraujo]

My brother and I are going to travel on a domestic flight, does he need an ID to travel?
FYI I am 18 year old 

[TheMiddleSeat]

No. It doesn't hurt to take a school ID if one is available just in case some TSA agent wants to be difficult and decides that the 14 year old looks older. 

--TheMiddleSeat