Assassination Classroom [Ansatsu Kyoushitsu] DVD Complete 1-22 + OVA + Special - Anime
A humorous and action-packed story about a class of misfits who are trying to kill their new teacher—an alien octopus with bizarre powers and super strength! The teacher has just destroyed the moon and is threatening to destroy the earth—unless his students can destroy him first. What makes things more complicated is that he's the best teacher they've ever had!
Ansatsu Kyoushitsu (OVA): Deai no Jikan
Koro-sensei reminisces about his first meeting with Karasuma, where they first butted heads and fought against each other, ultimately coming to respect one another. However, Karasuma eventually points out their actual meeting wasn't nearly as eventful.
Assassination Classroom, Ansatsu Kyoushitsu: Jump Festa 2013 Special
The story of the original manga begins after 70% of the moon was suddenly vaporized in an explosion. The super lifeform responsible for this catastrophe is a strange tentacled creature that can slink around at supersonic Mach 20 speeds. It has a 10 billion yen (US$100 million) price on its head, but for some reason, this creature ends up teaching a middle school class at the beginning of the school year. The students have until graduation to assassinate the teacher, or it will destroy Earth as well.
The event anime special adapts the original manga's popular segment about the field trip to ancient Kyoto.
NOTE: Special and OVA is Japanese Dubbed ONLY | 
