That happened last year, I laughed so hard xD

Same and Everyone in my class.

Was it because the teacher was angry?? xD

Nope. He did it for the fun of it. A teacher came to our class and told to be quiet because we were to loud. Our teacher was like "K" and put the rude finger up.

lol, teachers over here can get fired for even doing lesser things.

Got a funnier story. Student lit a teacher on fire. xD