Why do Slytherins cross the road twice?

Because they're dirty doublecrossers.

Why did Professor Snape stand in the middle of the road?

So no one could tell what side he was on.

What do you call a Hufflepuff with one brain cell?

Gifted.

What do you call a Hufflepuff with two brain cells?

Pregnant.

What did Harry's godfather say when Harry wouldn't stop poking him?

"Stop that now. I'm Sirius."

What is Draco's favorite taunt for first years?

Your mama's so fat the Sorting Hat put her in all four houses!

How do you know you're taking Harry Potter too seriously?

Your computer says "You've Got Mail" and you run outside looking for an owl.
You ask for a broom for Christmas.
You sort everyone you meet into the four Hogwarts houses.
You went out and bought the latest edition of the Webster's Dictionary because they added the word "muggle".
You were burned trying to get through the flames of your fireplace.
You were kicked out of the movie theater for standing on your chair, throwing your shoe at the screen and yelling "THAT DIDN'T HAPPEN IN THE BOOK!"

A blind wizard walks into a pub. He says to the barkeep, "Want to hear a Hufflepuff joke?" The pub goes completely silent. The barkeep says, "Sir, I am a Hufflepuff. I'm used to handling a rough crowd alone. I have my wand drawn. The wizard to your left is an auror with his wand drawn. He too is a Hufflepuff. The witch on your right has her wand drawn. She is a dueling champion and also a Hufflepuff. Are you absolutely certain you want to tell that Hufflepuff joke?"

The blind wizard says, "Gods no! Not if I'm going to have to explain it three times!"

What is Harry Potter's favorite pickup line?

I’d like to get my basilisk into your chamber of secrets!