I was confused on the exact timeline frame for Assassination Classroom.
I try to figure out the exact school year that Assassination Classroom (anime and manga) was in, and turns out it was very hard to say, although in the Live Action Movies, it was clear it was in SY 2015-2016.
The LA movies was premiered on 2015 and 2016, respectively, so it makes sense. But the anime, which was first aired in 2015, and the manga, which was first published in 2012, doesn't makes sense.
One of which is contradiction of one date to another.
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In Chapter 102, Koro-sensei keeps mentioning 7-1, and the Brazilians got angry over that. I had a deep research about it and turns out that the chapter 102 was published on July 28, 2014.
Apparently, it was based on the fact that on 2014 World Cup, Brazil was defeated by Germany 7-1 on July 8, 2014.
Unfortunately, it happened during July. And the Reaper Incident happened on October, which is Bitch-sensei's birth month (October 10). And it never makes sense. Maybe Matsui-sensei just wanted to insert a joke about the World Cup, or maybe the Brazilians in the manga was still salty about the loss months after. No offense.
The anime also included that fact.
Well, that makes the school year SY 2014-2015...right?
Wrong... Well, kind of wrong.
Chapter 112, the Hiromi Shiota incident. Published in October 2,2014. Do you notice the calendar on Hiromi's back. The narration says it was November. If Hiromi had changed the leaf of the calendar to fit with the new month, of course the date will show. If the calendar's week start on a Sunday... The closest will be November 2013.
So unless the calendar's week started on a Saturday, the school year will be 2013-2014.
2013-2014 and 2014-2015 are within the AssClass' publication date of 2012-2016. That is why Assassination Classroom universe has no clear date.
Correct me if I have mistakes on my point.

















