Malcolm: Reese, she's four years old. You're bigger and smarter... well, you're bigger than her.

Malcolm: Someone stole my friend's wheelchair.
Security Guard: What's it look like?
Malcolm: It's a chair... with wheels.

Malcolm: Someone's got to gi...
Reese: Not it!
Malcolm: Well, then, someone can mail it to her any...
Reese: Not it!
Malcolm: Well, someone's got to be the person to...
Reese: Not it!
Malcolm: ... not give it to her!
Reese: I'm it!
Malcolm: HAHA! ... Oh

Malcolm: That's not good, cougars don't just blow up!
Reese: As near as I can figure, I did it with my mind.
Malcolm: Reese! That's insane!
Reese: I wouldn't talk to me like that if I were you.

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 do you mean he's only seven?!
Nurse: What's not to understand? He just turned seven. I guess you were too busy beating people to notice!
Malcolm: He CAN'T be seven. He's bigger than I am!
Nurse: He's in second grade! [cleaning up Kevin] Look at all this blood...
Malcolm: That's not blood, it's pizza sauce! Well that's blood, but...
[Caroline Miller enters the nurse's office]
Caroline: Oh my God... OH MY GOD! What happened?
Kevin: [bawling] I want my Teletubby!
Malcolm: A doll?! You can't play with dolls if you're seven... WHY ARE YOU SEVEN?!
Caroline: You beat up a seven-year-old?
Malcolm: I didn't know!
Caroline: Malcolm, I don't blame you. I put this squarely where it belongs... [close to tears] On me!
Malcolm: [to camera] Oh, man. This is the most horrible thing I've ever done! [to Kevin] Kevin, I'm sorry!
Nurse: I think you've done quite enough.
Kevin: This is the worst birthday ever!

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 know, Francis, we never actually intended to show that letter to Mom. We were just trying to scare you.
Francis: I know, you guys would never do that to me.
Malcolm: But if she did see the letter, you know it was an accident, right?
Francis: Yeah, but Richie has the letter. Please tell me Richie has the letter.
Malcolm: Richie has coupons. Mom has the letter. But like I said, it was just an accident. I swear.
Francis: So the thing you were threatening to do all day but had no intention of doing you did, but didn't mean to?