Derek (to Casey): Good, because I don't want to hear how I am ruining your new job, yada yada yada, blah blah blah, (high-pitched) DER-EK!
S3 E6Don't Take a Tip from Me
Casey: Can't you see he's just buying you off with this fake generosity?
Lizzie: Well, where's my fake generosity?
Derek: Nobody talks that way to my step-sister, but me.
S3 E7The Bully Brothers
Derek: I'm not scrawny! I'm SCRAPPY.
Casey:(Dragging Derek down the hall) We need to talk!
Derek: And you need to cut your nails!
Casey: STOP THE VIOLENCE!
Ryan: We haven't started the violence!
Casey: Oh... okay. Don't start the violence.
Derek: (having been dragged in then out of the girl's bathroom) Wow, you guys have soap in there?
S3 E8Home Movies
Derek: Ms. Martinez, you cannot make me write this essay, I am a director, not a writer.
Ms. Martinez: I'm sorry, Derek but your proposal was very...
Derek: Entertaining?
Ms. Martinez: Silly. Edweirdo, the story of a household superhero.
S3 E9Show-Off-Tune
Casey: I can't look!
Emily: Yes, you can! You made the lead!
(Casey shrieks)
Emily: (winces) Yeah, I just hope your singing is better then your shrieking.
Max: So, who's my competition?
Casey: Max, guess what!
Max: You got the lead in the musical?
Casey: Who told?
Max: Like I'd ever go to a musical-
(Casey raises an eyebrow)
Max: That you weren't in!
Emily: Well, I don't know anyone who would be in a musical except . . .Derek?
Max: Derek?
Casey: DEREK!?
Derek: I'm not only in the male chorus . . .I am the male chorus. And at the after party all the chorus girls are going to be all over me.
Lizzie: I knew there was a reason.
Mrs. Z: Alright everyone, I want you to hold your diaphragm for breathing exercises . . . Derek hold your own diaphragm.
S3 E10Summer School Blues
Lizzie: I had to get peanut butter for Edwin to get Nosey and now there's no Wink in the sink!
Nora: Wink?
Lizzie: The skink.
George: In our sink?
Nora: Why is Wink the skink in our sink?
Lizzie: Stink.
These quotes come from Wikiquote's Life With Derek pages and are available under the Creative Commons Attribution-ShareAlike License.