you know he likes you when:

1.)whenever you walk by him he throws something at you
2.)he wants to sit near you
3.)when he gets in trouble he blames it on you
4.)when someone tells him to sit down he says he needs to tell you something (&& never does)
5.)he calls you names

you know you like him back when:

1.)you always tell him you are going to kill him (but you never do)
2.)you dont want to get too close to him
3.)when he gets in trouble you go with it
4.)you never ask him what he needed to tell you
5.)when you call him names back but cant say it with a straight face