at the start of class

Aizawa: "Class, we have a new student, he's also my son, so treat him well," he says in a threatening tone

The class looked shocked except for Bakugo Denki: "wait- YOU HAVE A KID?!" Mina: "Aww, dadzawa, that's so cute!!" Kirishima: "damn I didn't know that." Mineta: "I bet he's hot." Momo: hits Mineta on the back of the head Iida: "This is very surprising information. The whole class: "WHAT?!" You walk in!!