Malcolm: The tricky part is I need to keep this up without being put on medication.

Malcolm: Those guys are nuts. I'm funny!... Aren't I funny?
Lloyd: To be honest, you can be a little caustic.
Stevie: The word... is arrogant.
Dabney: How about bitter, sarcastic and handsome? (Lloyd and Stevie stare at him) (points somewhere) Hey, she's cute.

Malcolm: What sounds more idiotic: "Let's go to the desert, kids" or "Good idea, Dad"?

Malcolm: What's the point of being out here?
Reese: So you can find stuff like this. (picks up a dirty sock) Hehe, smells like gasoline.

Malcolm: When your TV privileges are taken away, you have to do something for entertainment. This is totally a trade-up.

Malcolm: Whoa, interesting dinner. Stevie beat the crap out of Reese, his dad got drunk, and his mom went totally psycho. Oh my god, we're contagious!

Malcolm: Why do I have to stay in the kids' ward?
Lois: I'm sorry, honey, but you're six months too young to have an adult room.
Reese: I hear if you're really good, they'll put apple juice in your sippy cup.

Malcolm: Why don't you just put a bulls-eye on my chest and get it over with?
Lois: Oh, you look fine. (The bells on Malcolm's costume jingle) And Reese will tell me if you take these off.

Malcolm: Yeah, and that kid, Josh, told everyone I was born with both sex organs and raised as a girl until I was five.

Malcolm: You're talking about joining a cult, Reese!
Reese: My name isn't Reese anymore.
Malcolm: Then what is it?
Reese: I don't remember, but it's not Reese!

Malcolm: [referring to Dewey] I don't believe this! Here I'm supposed to be the genius, and I'm being outsmarted by someone who can't tie his own shoes!

Malcolm:[first line] Ok, here's the thing about my family: we don't go on a lot of outings together. But when we do, there's a little tradition that we always end up observing.
Hal:[talking to the security guard] When you say lifetime ban, I mean who's lifetime that you're talking about.
[Lois drags Malcolm and Reese by the ear while the security guard sends Hal on his way.]
Lois: Don't you ever ask me for anything ever again. I should've just given birth to chimps, then at least I know to expect this kind of behavior.
Malcolm: Believe it or not, I actually envy Dewey. He got to stay home and play with the babysitter.

Mr. Woodward, Reese's history teacher: I just don't think you'd throw away the son who achieves for, well, Reese.
Lois: You don't think I'd sacrifice this one? Let me explain something to you. I would sell Malcolm down the river in a heartbeat to save Reese. Malcolm's gonna be fine no matter what happens. Maybe he'll have to go to junior college or start off blue collar, but he'll work his way up to management eventually. Reese is the one who needs saving.
Woodward: I don't believe you. No mother could ever be that callous to her own son.
[Francis appears in the window, pressed against the glass, while rain pours down and lightning flashes.]
Francis: Mom, please let me come home! I'm cold and I'm hungry! Please, I'll fix the roof, I'll paint the house! I'll do anything, Mom, please! Just let me live indoors, Mom! Please, I wanna be warm again! MOM, PLEASE! (sobbing)
[Lois smiles victoriously. Woodward looks rather apprehensive.]
Woodward: Maybe we can work something out.

Mrs. Griffin: (as she is driving, she feels an itch inside her cast and let's go of the steering wheel) Ooh, damn cast itches like a Greek sailor. (Malcolm tries to turn the wheel) Stop pawing at me!

Officer: There's no sign of forced-entry. You don't have any idea how they could have got inside?
Hal: It's a mystery.
Dewey: You left the window open.
Hal: ...Mystery solved!
Officer: What are you doing here again?
Hal: We're watching the owner's cat.
Officer: I don't see a cat.
Hal: We're not doing a very good job.