I don't like making fun of people, but with certain exceptions. My definition of making fun of someone and teasing are different, as teasing is kidding around and laughing with the person, and making fun is being a jerk with no regard towards the other's feelings. As for your situation, you could've said that calling him stupid doesn't help anything, but what do I know, I'm just myself.
You wanna know the worst thing that can happen at school? Playing capture the flag. I mean, the tackling, and the competition, and the enemy creating. I was on the opposite team of my best friend, and one guy got our flag, so I'm chasing him, and my friend blocks me so the guy scores, so I chase my friend across the field until he falls over and I throw grass at him. And the losers had to do twenty-five push-ups. Another friend of mine hid so hwe didn't have to do them. ... I talk too much.
If chickens had lips, could they whistle?