Middle schoolers are mostly kids that just hit puberty, and start getting really raspy voices. A large majority of them are kids that think they're tough, but in reality they're just cringey jerks. Not all of them are like this, but a large majority of them are like this.
Middle schooler: dude you're no match for me. I would knock you out without lifting a finger.
High schooler: dude you're still in middle school. Stop acting like you're strong.