Bartholomew "Bart" Simpson is voiced by Nancy Cartwright (that's right, a woman!) and is Homer and Marge's only son on The Simpsons.  Bart is an underachiever and was definitely much more of a bad boy in th ebeginning seasons of the show.

Now, Bart, although he has not aged, has certainly matured as a character.  Do the Bartman people.

Bart Simpson Quotes

Wow, now I see why they call you Miss Hoover. You must have been vacuuming for an hour.

Bart

Bart: Finally someone who does whatever I say!
Milhouse: Hey, Bart. I shaved my head like you told me.
Bart: Get lost!
Milhouse: Yes, master!

The Simpsons Quotes

Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side!
Man: (From inside a bathroom stall.) That's a right triangle, you idiot!
Homer: D'oh!

Mayor Quimby: And, uh, may the Force be with you.
Leonard Nimoy: You have no idea who I am, do you?
Mayor Quimby: Sure, I do. You're one of the Little Rascals, right?