Volume 17

Time for a Breakup (分裂の時間) is the seventeenth volume of the Assassination Classroom manga.

Preface
''Ever caught yourself screaming, "I could just kill that teacher"? What would it take to justify such antisocial behavior and weeks of detention? Especially if he's the best teacher you've ever had? Giving you an "F" on a quiz? Mispronouncing your name during roll call...again? How about blowing up the moon and threatening to do the same to Mother Earth—unless you take him out first?! Plus a reward of a cool 100 million from the Ministry of Defense! Okay, now that you're committed... How are you going to pull this off? What does your pathetic class of misfits have in their arsenal to combat Teach's alien technology, bizarre powers and...tentacles?''

Publisher's Summary
The class is divided: one half wants to carry on with the plan to assassinate Korosensei, while the other half wants to save him. So Korosensei splits them into two teams, led by Nagisa and Karma, and have them argue it out through an epic battle. The students of 3-E draw on everything they've learned so far to fight for or against Korosensei's life! Then to uphold their new unified goal, they need to infiltrate the International Space Station.