Thread:Kakarots/@comment-26091443-20180406202920/@comment-26091443-20180406203636

...No, students refer to each other by last name. Everyone in Class A calls Izuku, "Midoriya", everyone calls Katsuki "Bakugo", etc. In Japan, using "first names" is reserved only for the closets relationships. That's why the only person in the series who actually calls Izuku "Izuku" is his mother.

Like I said, I can just send you a link to the raws showing you the name order.