Principal Petersen: You better run, you little punk!

Sheldon: Attention, students and faculty. This is Sheldon Lee Cooper. We're taught that hard work pays off, but that's not true. I came up with a solution to save Earth from killer asteroids, and lost the science fair to SueAnn Ludlow, and her frizzy hair machine. But it wasn't just me who lost, we all lost. Wake up, people. The system's broken. Real innovation isn't valued. Nowadays, it's all about flash and style.
I blame MTV. Luckily, my parents can't afford cable. I urge you all to rise up. They can't send everyone to the principal's office. Chew gum in class, use a number one pencil, go nuts. This is Sheldon Lee Cooper signing off. Live long and prosper.

Diane: Sheldon Cooper's outside.
Principal Petersen: Who sent him now?
Diane: Givens.
Principal Petersen: Well, you know what? Givens needs to man up. Cooper's a little boy. It's not hard to handle him.
Diane: I'll send him in.
Principal Petersen: H-Hold on a minute, just Does he know I'm in here?

Sheldon: I was sent to see Principal Petersen.
Diane: What is it this time?
Sheldon: Youthful rebellion. My voice hasn't changed yet, but my attitude has.
Diane: I'll let him know you're here.
Sheldon: You do that. Ma'am.

Mr. Givens: How come?
Sheldon: Because I'm disillusioned with the school system.
Mr. Givens: Georgie, do you know what's going on with him?
George Jr.: Actually, I'm trying to ignore it.

Mr. Givens: So while an animal cell has a membrane, a plant cell has a membrane and a cell wall.
Sheldon: Who cares?
Mr. Givens: Sheldon, what are you doing?
Sheldon: Being disrespectful, sir.

George Sr.: Sheldon, listen, I know losing ain't easy. I deal with it on the football field all the time. It's like that big game we had last year against Nacogdoches. We were down 28 points at the half. It was raining, it was muddy. Everybody in the stands had gone home. But somehow, we managed to claw our way back to a tie with a minute left. And then, they threw a Hail Mary, and the receiver stepped out of bounds, but the ref didn't see it. After all that, we lose on a bad call. Believe me, I was furious. But I sucked it up, and I walked across that field and I shook their hands.
Sheldon: I didn't hear a word you said.
George Sr.: Okay.

George Sr.: You don't always win in life, he needs to learn that.
Mary: I know, but these are big feelings for a little boy.
George Sr.: They're feelings everybody has. It's part of growing up.
Mary: I guess.
Sheldon: Poodle poop!
Meemaw: Okay. Somebody's got to teach this kid to swear, it's embarrassing.

Mary: I hate to see him so upset.
George Sr.: Well, give him a little time, he'll calm down.
Sheldon: [door slams] Fiddle-faddle!
Meemaw: The F word. He's real mad.

Sheldon: I'll be in my room.
Mary: Oh, come on, Shelly. You still got an honorable mention.
Sheldon: Stop reminding me.

Principal Petersen: And the winner of the Medford High School Science Fair is SueAnn Ludlow!
Sheldon: You've got to be kidding me!
Mary: Shelly.
Sheldon: You people are crazy!
George Sr.: Hey. All right.
Sheldon: You're celebrating mediocrity. Mediocrity! Mediocrity!

Adult Sheldon: On any given day, our school gymnasium presented a cocktail of horrors. From daily humiliation to school-sanctioned violence. But one day a year, the gymnasium was transformed into a haven of learning thanks to a remarkable institution known as the science fair. A chance for the student body to come together in the name of research and progress. Uh, while some did the bare minimum, and others preferred razzamatazz over raw data, I set out to save humanity from deadly asteroids.
And made it all neatly fit on three poster boards. The science fair may be a competition, but when the goal is promoting knowledge, we're all winners.

Adult Sheldon: As you can see, sometimes a person can be both incredibly intelligent and full of baloney.

Sheldon: I've been giving geology some more thought.
Tam: Yeah, and?
Sheldon: I've decided it's not really a science.
Tam: It's not?
Sheldon: No, it's more like a hobby. Rock collecting. Childish, really.
Tam: I can see that.

Tam: It got a little uncomfortable.
Sheldon: Why is that?
Libby: Libby's got feelings for me, but I think it's better we just stay friends.

Libby: What are you doing?
Tam: What do you think I'm doing?
Libby: Move your arm before I rip it off.

Sheldon: Regardless, I'm not interested in making any more friends.
Mary: Oh, I don't think that's how you really feel.
Sheldon: It is. From now on, it's a hermit's life for me.
Mary: I bet, when you grow up, you will be surrounded by lots of smart, wonderful friends.
Sheldon: I can't see that happening.

Mary: Where were we?
Sheldon: Different kinds of maturity.
Mary: That's right. There's emotional maturity, physical maturity, all things that have nothing to do with being smart.
Sheldon: Are you suggesting I'm not emotionally mature?
Mary: I was hinting at it.

Missy: What's up?
Mary: None of your business.
Missy: Why is he crying?
Mary: Again, it's none of your business. Please go.
Missy: Fine. Celeste and I know when we aren't wanted.

Mary: She is almost twice your age.
Sheldon: There are people five times my age that are stupider than me.
Mary: This is not about being smart.
Sheldon: What else is there?
Mary: Well there's other kinds of maturity.