She clutched the iron;
"This diamond shaped iron you see here is not my creation. Not at all, it was given to me as a gift by my boyfriend Alex!"
As she said that last part, she shot Zooey a knowing look that said; 'that's right bitch. MY BOYFRIEND.'
Zooey got the message alright, and she got it good. Basically, Scarlett had just declared to the world that she and Alex were together. Given the fact that this was a school, and a closely knit community, gossip was certain to flow later on. Some people knew that in recent times, Zooey was rumored to be seen frolicking with this Alex character.
So, by publicly stating that Alex was her boyfriend, Scarlett had single handedly crucified all those rumors. And also made Zooey look exactly like what she was- a side chick. Nothing more. It was a brilliant maneuver really. She now had the affection of the crowd, as well as their empathy. Zooey had neither the boyfriend, nor the victory.