A new Assassination Classroom game titled Assassination Classroom: Assassin Training Plan!! has been dated for a March 24, 2016 release on Japanese 3DSes, with the release being intended for physical and digital versions,
According to the announcement, Assassin Training Plan!! will task players with stepping into the shoes of a Class 3-E student, where they must take part in school events, tests, and more while trying to assassinate Koro-sensei under the time constraints.
Source: Shonengamez.com (via Crunchyroll)