People really should stop talking about the Attacker. If you do, you give him exactly what he wants, you all are kinda enabling such fucked up things.
People who do things such as this, usually do that because they want their minutes of fame, if you give them that, by talking about them, by posting their names, online accounts and photos, you're giving them what they want and other people with a similar mind may see that it is working and start imitating it.
Its called werther effect.
Talk about the victims that died because they deserved to be remembered, especially when they died protecting others like the teacher did, and talk about the issues that may have led up to such a cruel thing happening so they may can be solved at some point, but do not talk about the attacker if avoidable.
Anyways, my sympathy goes out to the kids, teachers and familys of the victims. Living through such an attack must surely be a bigger horror than anything one could imagine, i hope the kids dont end up too deeply traumatized by it.