The race around the school, when Takasu finally puts his angry face for good, not to mention Minorin helping him in the end, with a Double Knockout by a baseball ball.
Episode 16 ends on a particular high note. After Kitamura is rejected by Sumire, Taiga becomes furious and pulls a bokken out from her shirt, goes to Sumire's classroom, charges at her atop the desks and then proceeds to have a fake-sword battle against Sumire as they beat the crap out of each other.
The swords are fake. The battle, not so much. Both girls' faces are visibly swollen and bruised and have to be restrained by other classmates.