I agree, he wasnt an on the streets type thug kid from what Ive read, but new details paint him a little darker than that

From someone at the school:

'Apparently the boy hid in school after class, he didn't go home at all. Then I heard he forced her into the bathroom and attacked her with a knife from the art room.

'People are saying he then dragged her down the stairs and got rid of her body in a recycling bin. No one has any idea why he did it. It is a tragedy.'
this hasnt been confirmed