Sheldon: But what if it's scratchy and it's all I can think about?
Dr. Linkletter: It's just armpit hair.
Sheldon: Well, I don't even have it yet and it's already consuming my thoughts.
President Hagemeyer: All right, Sheldon, you are a smart kid. Now, you had to know that this was gonna happen eventually.
Sheldon: I'm a smart kid now, but what will I be in a year?
President Hagemeyer: A smart young man.
Sheldon: And then a smart adult. With money problems and marital strife and every other problem you can think of. I'll probably have a beer belly. Or root beer belly.

Principal Petersen: Our next young speaker needs no introduction, but that didn't stop him from writing one and making me read it. [laughter] "Fun fact." [audience groans, murmurs] I hear you. "The word 'valedictorian' is from the Latin 'valedicere,' meaning 'to say farewell.' It is primarily used in the United States, Canada, the Philippines and Armenia." Maybe that fact's more fun in Armenia. Please welcome your valedictorian, Sheldon Cooper.
Mary: Yay, Shelly!
Sheldon: Hello. I'm not very comfortable speaking in front of crowds. But there's a technique to reduce stage fright by focusing on one person in the audience and delivering your speech just to them. That's what I'll be doing today. If it weren't for this person, I wouldn't be here right now. They've taught me a lot, and it's by their example that I found the courage to move forward into this new and exciting chapter of my life. Missy... ...this is for you. Change can be scary, but I know we're going to be fine... ...because like you said, "It's okay to be scared. We just have to do it anyway." So if any of my fellow graduates are nervous about the future, know that you're not alone. I suggest you all try to be as brave as my twin sister. That's my plan. Missy, I wish I could give you advice about middle school, but I was so smart, I skipped it. If you make it to high school, we'll talk. Thank you. [applause]

Missy: What's it like to not believe in God?
Sheldon: It's great. Big fan.
Missy: Are you ever afraid you're wrong?
Sheldon: About religion? Never. About other things? Also never.

Ms. MacElroy: Now, can anyone tell me why Melville shifts the narrative voice from Ishmael to Ahab? [Ms. MacElroy waits for somebody else to raise their hand] Sheldon.
Sheldon: I have a tummyache. I'd like to see the nurse.
Derek: A "tummyache"?
Sheldon: Yes, Derek, I have a tummy and it aches. Ergo, tummyache.
Derek: Ergo?
Sheldon: It's Latin, Derek.
Ms. MacElroy: Go to the nurse.
Sheldon: And to answer your question, the shifting point of view grants the reader a broader perspective of events than typically allowed by first-person narration.
Ms. MacElroy: Where were we?
Sheldon: And "ergo" is Latin for "hence," Derek.

Adult Sheldon: [hushed] This is why the only bar I frequent is the Genius Bar at the Apple Store.

President Hagemeyer: Okay, so, what's the problem?
Sheldon: I wanted to talk with Dr. Linkletter about puberty.
Dr. Linkletter: And I wanted to avoid litigation.

Missy: Sheldon, there has to be stuff you're excited to do.
Sheldon: Of course. Getting my PhD, winning the Nobel Prize, getting to meet Professor Proton, working with Stephen Hawking.
Missy: Okay, so, when you start to get upset, focus on that stuff.
Sheldon: But... what if I grow up and none of those things ever happen?
Missy: All you can do is try and find out.
Sheldon: Those are the fundamentals of the scientific method.
Missy: No doy.