The exams climax with a showdown between Karma and Gakushu as they tackle a difficult maths problem, which Karma discovers is easier to solve than he initially thought. Following the exams, it is revealed that all E Class students managed to land in the top fifty, with Karma placing first. After Gakushu and the rest of A Class state their preference to E Class' ideals, Gakuhō takes matters into his own hands, threatening to destroy E Class' campus and sack Koro-sensei. In order to save the class and his job, Koro-sensei is tasked with solving textbooks containing anti-sensei grenades, with one book containing a real grenade.