Adult Sheldon: That was the first time I held my father's hand. I wouldn't touch my brother's hand until seventeen years later, thanks to the invention of Purell.

Mary: You understand that some people are going to be intimidated by you, because of how smart you are?
Sheldon: Or maybe they'll recognize my intellect and make me their leader.

Mary: How about we lose the bow-tie?
Sheldon: Why?
Mary: Look around, honey. No of the other kids are wearing one.
Sheldon: Well, perhaps I'll start a fad.

Pastor: In Matthew nine, verse four, Jesus said, "Why would you entertain evil thoughts in your hearts?"
Sheldon: Do you have evil thoughts?
Mary: Ssh.
Sheldon: I just don't think this part applies to me.
Mary: That's fine. Be quiet and listen.
Sheldon: I'm only nine years old. Most evil doesn't start till puberty.

Sheldon: I smell ammonia. They must've done a thorough cleaning recently. I like that.

Adult Sheldon: Jane Goodall had to go to Africa to study apes. I just had to go to dinner.

Sheldon: Per the student dress and grooming code, this boy's hair is too long. This boy's wearing sports attire outside a designated area. And this girl's blouse is diaphanous, which means I can see her brassiere.

George: You're not gonna make it in this school if you keep ratting people out.
Sheldon: But they were breaking the grooming codes and the dress codes. I saw one boy with a t-shirt that said... [leans in and whispers] "Bite me".
George: Yeah, that's terrible. [Sheldon nods]

Sheldon: Mom, when should I be expecting my testicles?
Woman: [turns around] What is wrong with him?
Mary: Nothing is wrong with him. Now turn around before I knock your lights out.
Sheldon: Hello.

Adult Sheldon: I've always loved trains. In fact, if my career in theoretical physics hadn't worked out, my backup plan was to become a professional ticket taker. Or hobo.

George: What the hell were you doing out there?
Mary: George, language.
George: What language?

Mary: Everybody excited to start school Monday?
Sheldon: I am.
Missy: I guess so.
Mary: Georgie? Freshman year, that's a big deal.
Georgie: How can I be excited when he's gonna be in the same grade as me?
Sheldon: Don't worry, Georgie. I'm not planning on being in the ninth grade for very long.

Sheldon: I was exploring dimensional kinematics.
Georgie: Admit it. He's adopted.
Sheldon: How can I be adopted when I have a twin sister? Think, monkey, think.

Ms. MacElroy: What?
Sheldon: Also in violation of the grooming code on page 48, article five, subsection B, you have a bit of a mustache.

Mary: That's enough. Now, let's pray.
Sheldon: A moment please.
George: Hmm.
Mary: Leave him be.
George: He can hold hands with his family. It won't kill him.
Sheldon: We don't know that.