Sixth Period: Before & After Time

Riding high after the pole-felling win, Class E grinds toward mid-terms while restless about the five months left to kill Korosensei. Trying to study and sharpen their skills at once, most of them parkour across rooftops toward the train station. Near the end, Okajima and Kimura leap down and crash onto an elderly cyclist, breaking his leg while a young man with flowers calls an ambulance.

At the hospital Karasuma reports the injury as his subordinate tries to buy the man's silence, since the students are a national secret. A furious Korosensei arrives and slaps each of them with a tentacle, and Karasuma, feeling partly to blame for rushing their training, lets it slide once. Korosensei bars everyone from studying for two weeks, framing it not as punishment but as a lesson in aiding those weaker than themselves.

The class is sent to run the man's nursery while he recovers. The building is decrepit but underfunded, since he charges parents almost nothing and does most of the work himself. The students split duties, rebuilding the structure from mountain wood using a blueprint Ritsu obtains while others mind the children. Nagisa sits with Sakura, a withdrawn older girl skipping elementary school over bullying, and gently tells her that learning from the ground up lets a person climb higher and shed the fear of heights, urging her to return once she has a plan.

Two weeks on, the recovered principal is stunned to find a fully overhauled nursery with a new second floor, library, playroom, and garage, plus a bicycle rigged with his old dentures as a bell. Sakura excitedly reports placing second on a math test by attending only for the exam, and Nagisa promises to keep tutoring her. Back at school, mid-terms leave most of the class ranked lower while the Big Five reclaim the top, though Karma gloats about reaching second overall behind Asano. In the staff room the class tells Karasuma they have learned to use their skills to help others rather than show off, and they surprise Korosensei in new government-issued military uniforms, vowing to protect people with them.

The sixth season-two episode adapts chapters 95 through 98. In a manga difference, the students showed off their new gear in several ways before Karasuma explained the situation to Korosensei. It first aired in Japan on February 11, 2016, with the dub on March 16, 2016.