It all 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.
Source: Assassination Classroom on Kissasnime
About
Assassination Classroom or commonly known as Ansatsu Kyoshitsu is a Japanese comic science fiction manga series written and illustrated by Yūsei Matsui. It was published by Shueisha from July 2012 to March 2016. It was later adapted into an anime series by 2015 running for two seasons by Lerche Studios.
Thoughts
Assassination Classroom starts off with a literal BANG! when a tentacled creature vaporized 70% of the earth's moon permanently making it into a shape of a crescent. The creature then threatened humankind by saying that within a year he would also do the same thing to Earth. He then offered humankind the only way to prevent all this from happening, which is simply just to KILL him.
Obviously if it were that simple, we wouldn't have a two season anime, right? Killing the tentacled creature seems to be an impossible task for ordinary humans. Not only can he move at Mach 20 speed, to which I check means 20 times faster than the speed of sound. He also has awesome reflexes, a genius intellect, regeneration and camouflaging skill and an absolute defense. Even a nuclear bomb wouldn't do anything to him.
To give mankind a shot at killing him. The tentacled creature to which we would now call as Koro-sensei (a combination of the japanese word 'korosenai' meaning unkillable and 'sensei' as teacher) volunteered to become the homeroom teacher of a bunch of misfit students teaching them the art of assassination. The government then issued a ¥10Billion (around 100 million USD) to whoever among the students can successfully kill him.
Despite sounding like a bloodthirsty, gory, violent twisted anime, Assassination Classroom is surprisingly a lighthearted one. Korosensei is not as evil as one would think. He is a pretty decent guy who just want whats best for his students despite the whole destroying the planet Earth thing.
The show teaches us moral and life lessons as what you would expect in almost all student-teacher relationship genre. Korosensei makes this bunch of misfit students better people one at a time It is also good to note that comedy is also all over the place making it more entertaining and not too boring to watch. The show however relies too heavily on comedy that the story seems to be lacking. Overall I give it a 7.5/10.