The Cheerleading Competitions was an event which happened in Bring It On.
Elena's emotions are off and we see a different side of her. Elena makes her first act of cruelty at the Mystic Falls High School cheerleading competition, where she fed on a cheerleader and stole her ribbon. When Stefan confronts her she rebuffs him. Caroline tries to stop her from competing but Elena challenges her to make her stop. She also tossed Caroline into the air and casually dropped her during the team's cheerleading routine (possibly as revenge for Caroline's earlier action). Outside, Stefan vervains Elena and takes her to his house.