Mouthy 9 year old- suggestions??

I have a mouthy 8yr old son ( he has always been this way). He got in a ton of trouble at school today (name on the board 4x's, sent to the principles office a week of lunch detention AND a call to me). After DH talked to him about it T went to his room and mouthed off "If you think I was mean today you just wait". Dh quickly informed him HE can be much meaner and he was real close to having nothing in his room but a pillow and blanket in the floor. Of coarse T goes from acting like a mouthy teen to crying like a todder.