Penny is reluctant to tell Leonard that she is taking a history class at Pasadena community college. After he finds out, Leonard reads and then completely rewrites her paper on slavery. Sheldon is playing the on-line game Words with Friends with Stephen Hawking on line.
Howard and Raj are dancing to Star Wars characters using the Galactic Dance Off video game. They think they look cool, but Leonard tells them that they look the same way at their dance clubs. Sheldon announces that he has begun playing Words with Friends with Professor Stephen Hawking, making them friends. Now all he needs is a bed with a slide and he’ll have everything he's wanted since he was six years old. Leonard is very happy for him. According to Sheldon, the other guys should be happy because they are a friend with an official friend of Stephen Hawking and that they have may have now “peaked”. Howard notes that he did work with him. Sheldon engages Hawking in the game on his Apple iPad. After Professor Hawking makes his first move, Sheldon feels that now they’ll start making up fun nicknames for each other. He’ll be “Coop” and the Professor will be “Wheels”.
Penny, Amy, and Bernadette are hanging out at Penny’s apartment where Bernadette tells them that she found herself drying her body off with Howard’s mother’s underwear. She immediately took another shower that wasn't enough. Amy got a thrill when she got a look in Sheldon’s underwear drawer. Bernadette finds Penny’s history textbook for a class that Penny was taking at Pasadena City College. She was just trying to go back to college. Amy also mentioned that her acting career was going south like Sherman and that she could read about it in her book. She hasn't told Leonard because he’ll get all excited about it, be so proud of her and try to help her which makes her gag. Amy tells her that they are the weirdest couple she knows. Penny asks her if she can’t think of anyone else weirder, to which Amy whispers that she could, but she was sitting there, referring to Bernadette.
While Sheldon is playing Words with Friends, Amy is happy that her boyfriend is friends with Stephen Hawking and her new dandruff shampoo doesn't smell like tar so everything is coming up “Amy”. Sheldon tells Amy that he is badly beating Professor Hawking, to which Amy comments that when one man dominates another, it can raise their testosterone level. Sheldon doesn't get the point. Amy thinks it’s exciting that Sheldon might even be getting a testosterone level. He is now calling the Professor "Stephen" because he did not like “Wheels”. Amy suggests “extract” as Sheldon’s next word, though he objects because it would be cheating if he didn't think of it. He decides to use the unrelated word “extract” (different pronunciation).
Leonard and Penny are eating spaghetti at Penny’s apartment that is a bit crunchy since she didn't boil the water enough. Penny tells him about her history class which Leonard tells her is great, but she doesn't want him to make a big deal out of. Leonard goes on about full time college and transferring to a four year school and Penny cools him down with “you’re making it a big deal”. She thinks the class is going real well and that she has to turn in her first paper on the origins of slavery. Leonard suggests several perspectives and Penny feels her perspective is that slavery is bad especially since she has a black instructor. Penny won’t let him see her paper, though later he does have a chance to sleep with a college girl. Leonard replies that that is great since it never happened to him when he was in school.
During dinner in Sheldon’s apartment, Raj tells them that he wants to develop an American accent when he calls an Indian call center since he feels his own voice sounds like he is making fun of them. Howard feels that his new accent sounds like he taking with dentures. Sheldon is lamenting that fact that Professor Hawking hasn't made a move for three days in a game that Sheldon was humiliating in. Howard remarked that the Professor is a big baby and doesn't like to lose. After Howard had corrected him about Johnny Depp not being in the Matrix movie, Howard didn't get invited to his staff pizza party.
That night, Leonard slips out of bed with Penny and reads her paper on her laptop. After a couple of ‘a hems’ Leonard decides Penny's writing is just as terrible as the spaghetti she made for dinner. Leonard goes back to his apartment and finds Sheldon using the Jedi mind control trick to get Professor Hawking to play. Leonard tells him that he did a bad thing by reading it behind her back. Sheldon tells him about Hawking not playing. Since they are talking about different subjects at the same time, Leonard pulls out the chess timer and that they will take turns discussing their problems. Leonard tells Sheldon to give the Professor some time and Sheldon doesn't care about his problem with Penny, as his only advice is: "Women, Huh?" Leonard leaves in frustration to which Sheldon tries to get him back with the Jedi mind trick. It seems to work when Leonard hears his name mentioned, though Sheldon figures it’s because it only works on the weak-minded.
In the morning at 8 AM, too early for Penny, Leonard shows up with breakfast in bed and a folder on the tray. Leonard gives her the story of the "Shoemaker and the Elves" and leads into giving her a new history paper. Penny replies that it’s too early for The Lord of the Rings. Leonard’s point was that the shoemaker was not mad at the elves for making all these wonderful shoes. Penny says that he assumed that the paper would be bad and then wrote her a new one. Leonard replied that he assumed that it would be good and then read it. She found that he had changed every word and then Leonard pointed out the years listed, the word slavery and her name hadn't changed. Penny calls him an ass and that that was why she didn't want to tell him in the first place. Leonard explained that he just didn't want her to get a bad grade, get discouraged and quit school. Penny turned it around that her being in school was so important to him and that he didn't want to date a girl that was just a waitress. She has to do it herself whether she passes or fails. Finally she tells him that this story is not the Shoemaker and the Elves story, it is the one where you give a man a fish and he eats it or you teach him and then she gets the analogy confused and slams the bathroom door behind him.
At the Caltech cafeteria, Raj and Howard commiserate with Sheldon over not playing with Professor Hawking. Sheldon comments that the man is a genius with the voice of a robot and who could be a better friend than that. Raj comments that if he is a sore loser, then maybe he isn't that good of a friend. Sheldon agrees and says that he'll just have to make lemonade out of the two of them as friends implying that they are lemons. Finally Professor Hawking takes his turn. Sheldon is excited to be playing again with “Rolling Thunder” which is an acceptable nickname. Sheldon debates whether to throw the game with a little word to remain his friend or do the correct thing and win. Finally he decides to let Professor Hawking win.
Penny shows up at Leonard’s door after they had not seen each other for a couple of days. Leonard wonders if she was still mad at him. Penny says that there was no reason for her to “B” mad at him. Minus. She presents a “B-“on her paper. She says that it was on her paper and not his “you punk ass elf” and she then proceeds to mock Leonard (while making herself sound stupid) by saying that she may be taking that class, but he learned the lesson that she was smarter than he thought. She leaves and then returns to Amy and Bernadette in her apartment. She says that she doesn't think that Leonard will be making that mistake again. She also tells the girls that if they ever tell Leonard that they helped her with the paper, that she will beat each of them with a bag of oranges. They both agree. Penny then explains that next time maybe they can put their heads together and get an A. Bernadette explained that her “B-“was on purpose to make it believable. Penny snapped back that they didn't think that she was smart enough? “No, no”, the two girls replied in unison after Penny’s bag of oranges comment. “Good” she finished. The girls felt like they were back in high school doing the prom queen’s homework so that she would like them. Amy finished with that it was finally working.
Finally, Sheldon gets a phone call from Stephen Hawking. He thanks him for the game and calls him Dr. Cooper or Dr. Loser. Sheldon congratulates him on winning. Prof. Hawking asks him if he likes brain teasers. "What do Sheldon Cooper and a black hole have in common? They both suck. Neener, neener." Leonard, who was present, laughs his arse off upon hearing this.
- Guest starring:
- Stephen Hawking as Himself (Voice Only)
- Teleplay: Steven Molaro, Jim Reynolds & Eric Kaplan
- Story: Chuck Lorre, Bill Prady & Steve Holland
- The TV Critic: "Both stories demonstrated the show’s weaknesses. Ask yourself what story was being told with Penny and Leonard? Was it about her quest to improve herself? Kind of. Was is about their relationship? Kind of. Was it about him as a boyfriend? Kind of...The Sheldon story was just more stasis. The writers are so un-ambitious that they use the idea of Stephen Hawking (and his voice software) to tell the most basic and predictable of stories...Yeah I know, why am I reviewing a show that is committed to maintaining the status quo no matter what? I ask myself every other week."
- The A.V. Club gave this episode a B+.
- IMDb user reviews
- Title Reference: The title refers to the word 'extract' played by Sheldon.
- Chuck Lorre's vanity card.
- This episode was watched by 15.90 million people with a rating of 5.2 (adults 18-49).
- Total viewers including DVR users 19.84 million.
- This episode aired in Canada on November 1, 2012 with 4.222 million viewers and a weekly ranking of #1.
- In the United Kingdom, this episode aired on December 20, 2012 with 2.732 million total viewers.
- Episode transcript 
- Sheldon wears his red "Kablaam" computer shirt, available from The CBS Store.
- Penny's yellow and purple "Liz" dress by Tahari is no longer available from Bluefly.
- Raj and Howard engage in a Galactic Dance Off with Boba Fett and stormtroopers in Kinect Star Wars. They are playing it on a Limited Edition Kinect Star Wars Bundle of XBox 360 - in fact, this game comes with this bundle.
- The sequence at the end of the teaser where Kunal Nayyar takes off his shirt was not part of the script. In fact, he was only trying to take off the sweater, but the shirt unexpectedly came off too and he ran with it expecting it to be in the blooper reel.
- Stephen Hawking speaks in this episode, thus, he is a cast member once again, following being in "The Hawking Excitation" (S5E21) episode.
- Bernadette only has two Apartment 4B scenes with Penny and Amy in this episode.
- Amy only has one scene with Sheldon in this episode and she has two Apartment 4B scenes with Bernadette and Penny in this episode.
- Leonard shares no scenes with Bernadette and Amy in this episode.
- Sheldon shares no scenes with Bernadette in this episode.
- Sheldon has no speaking parts with Penny in this episode, despite them appearing briefly together.
- Howard and Raj share no scenes with Amy, Bernadette and Penny in this episode.
- Sheldon engages Stephen Hawking in Words With Friends (a free app) on an Apple iPad.
- In the end, though trying to genuinely help regarding his game with Hawking, Raj and Howard support everything Sheldon decides, just like Leonard does in "The Monopolar Expedition" (S2E23).
- Amy states to Sheldon, "You know, when one male dominates another, his testosterone level rises. It’s exciting to think you might be getting a testosterone level." She is clearly amazed by Stephen Hawking and is more attracted to Sheldon as he dominates him. Her reasoning is somewhat similar to that heard by Penny in "The Higgs Boson Observation" (S6E3). As an expert in neurobiology familiar with primate psychology, she frequently provides such analysis in numerous episodes, but this propensity does not phase Sheldon much, such as also seen in "The Rhinitis Revelation" (S5E6). On the other hand, Sheldon resorts to more abstract philosophical thought, e.g. in the pilot (S1E1: "proximal and distal causation") and "The Good Guy Fluctuation" (S5E7: "moral philosophy"), yet unlike "The Maternal Congruence" (S3E11: Weltschmerz)
- Leonard is revealed to have attended college for four years and graduate school for five years, like David Saltzberg. This fact is a normative time for completion of the respective programs, but it was probably intended in the production that Leonard was twenty-seven years old when he received his Ph.D, with the writers forgetting what had been cited in "The Cooper-Hofstadter Polarization" (S1E9). Since Leonard earned his doctorate at twenty-four years old and was not a prodigy entering college at fifteen years old, the posited scenario necessary to avoid an inconsistency is that he earned an additional graduate degree after his doctoral degree. In "The Bad Fish Paradigm" (S2E1), Penny even stated, "Well, he was going on and on about this college and that grad school and I didn't want him to think I was some stupid loser." Notably, by the timeline set in the pilot, Leonard would have already completed the supposed degree. Refer to "The Staircase Implementation" (S3E22) and "Leonard Hofstadter: Trivia" sections for more information on Leonard's prior education.
- Penny again bullies her closest friends Amy and Bernadette.
- Second episode where a character sneaks into Penny's apartment to improve something of hers while she is sleeping much to her annoyance. First was "The Big Bran Hypothesis" (S1E2).
- Penny did not cook spaghetti well for Leonard in this episode, however, in "The Spaghetti Catalyst" (S3E20) did a fine job cooking it for Sheldon..
- Stephen Hawking: What does Sheldon Cooper and a black hole have in common? They both suck. Neener neener.
- Leonard: Oh, hey. Haven’t heard from you in a couple days. You still mad at me?
- Penny: Nope. I have no reason to… “B” mad at you. Minus.
- (the scene in Penny's bedroom where Leonard is bringing Penny some breakfast on a tray. he bends down for a little bit to Penny's sleeping face)
- Leonard: Good morning, sunshine.
- (Leonard puts the breakfast tray on the bed next to Penny)
- Penny: (she's not pleased to be woken up) Leonard. It’s eight a.m. It’s like the middle of the night.
- Leonard: I know, but I have to go to work, and I made you breakfast.
- Penny: Oh, wow, that’s so sweet. Hey, what’s this?
- Leonard: Uh, before you open that, um, are you familiar with the story of The Shoemaker and the Elves?
- Penny: Elves? (she's now very cross) Come on, Leonard. It’s too early for Lord of the Rings.
- Leonard: No, no. Listen, um, once upon a time, there was this shoemaker and when he went to bed at night, elves would sneak in and they would make all these amazing shoes for him. And when the shoemaker woke up in the morning, he, he would be super happy, not mad at the elves at all. Open it.
- Penny: Okay. An examination of the economic, cultural, and political roots of slavery in the Old South, 1619 to 1865. (she's asking Leonard crossly) What the hell is this?
- Leonard: Don’t ask me. A little elf did it.
- Penny: So let me get this straight. You just assumed my paper would be bad so you wrote one for me?
- Leonard: No, I assumed it would be good. Then I read it.
- Penny: (she shrieks at Leonard) What?
- Leonard: No, I, I mean, it was good. There were just a few things that needed a little polishing.
- Penny: You changed every word.
- Leonard: That’s not true. Uh, slavery. 1619. Your name at the top. That’s all you.
- Penny: (she's even more crosser) You are such an ass. This is exactly why I didn’t want to tell you I was taking a class in the first place.
- Leonard: Please don’t be upset. I just, (Penny sighs with anger) I didn’t want you ending up with a bad grade and get discouraged and give up on the idea of going back to school.
- Penny: Right, because me being in school is so important to you. That way, you wouldn’t have to be dating someone who’s only a waitress.
- (Penny now gets out of bed in such fury)
- Leonard: Oh, come on, you know that's not true.
- Penny: (she shouts at Leonard) Do I? Listen to me. I need to do this on my own. If I fail, I fail. Do you get it?
- Leonard: I'm sorry. I was just trying to help.
- Penny: (she is still completely angry) Yeah, well, next time don’t. (she slams the bathroom door and reopens it to lose her final angry pieces at Leonard) Oh! and since you like stories so much, (Leonard reacts at Penny shouting) this is not The Shoemaker and the Elves, okay? (scene of Penny still shouting with huge anger) This is, give a man a fish, he eats it. Teach a man to fish, he, sells it or something. Whatever, I don’t know, it’s just a lot better than what you did, you big jerk!
- (Penny storms into the bathroom. Leonard reacts at the sound of door slamming in his face and he now thinks for a little bit)
- Sheldon: Good lord. What have I done?
- Raj: (In an American accent) Good lord. What have I done?
- Howard: Terrible.
- Leonard: (Puts chess time out of the box) Okay, here's what we're gonna do. Chess clock. We each get five minutes to talk about out problems. We'll take turns. (Places chess timer in the table) Each turn will consist of a statement and a helpful response from a friend. (Presses button) Begin
- Sheldon: I humiliated Stephen Hawking in a game of "Words with Friends". He stopped playing, and now we're not friends anymore.
- Leonard: He's probably busy. You're worried about nothing. Give it a couple more days. I'm sure he'll play, and you'll see that everything's fine. (Presses button) My turn. I can't let Penny hand in a bad paper, but how do I tell her it's bad without letting her know that I read it?
- Sheldon: Hmm. Beats me.(Presses button) Now, I know Hawking's not busy because I can see he's playing other people right now.
- Leonard: Maybe since you're so good, he's taking his time to meet the challenge. (Presses button) I want Penny to enjoy school...
- Sheldon: (Presses button) Wolowitz told me he's a big baby. But I didn't know that, and I played "Extract" for 82 points. It's all Amy's fault. She told me to play it. I have to cut her loose.
- Leonard: Sheldon, I wasn't done talking. (Presses button) She hands in the paper tomorrow. I know I could help her. And she's my girlfriend; I should be allowed to help her. Why aren't I allowed to help her?
- Sheldon: Yeah, I hear you, brother. (Presses button)
- Leonard: No. (Presses button) You need to give me some advice.
- Sheldon: Fine. Women, huh? (Presses button)
- Leonard: (Presses button) Specific to my situation.
- Sheldon: Blonde women, huh? (Presses button)
- Leonard: (Presses button) Empathetic.
- Sheldon: Sucks to be you. (Presses button)
- Leonard: (Presses button) I quit. (Goes to his room)
- Sheldon: Leonard, wait, no. I listened to your dumb thing.
- Raj: Dude, my accent is brilliant. (In American accent) Hey, my snow-white American friends, let's put some cow meat on the barbecue and eat it until we're all obese.
- Howard: This is what you sound like. "I think I'm talking in an American accent, but it really sounds like I'm wearing a set of giant dentures."
- Raj: Sheldon, do I really sound like that?
- Howard: Tell him he sounds like that.
- (Scene of Bernadette complaining during girls time at Penny's apartment)
- Bernadette: (she is so not vey happy) So, I was taking a shower this morning, and when I got out, I started to dry off with what I thought was a towel but turned out to be Howard’s mom’s underwear. I had to take another shower. It wasn’t enough. Nothing will ever be enough.
- Amy: I once looked in Sheldon’s underwear drawer. He yelled at me. But now I know what it looks like and he can never take that away.
- Bernadette: There’s a book under here.
- Penny: Oh, I’ll get that.
- Bernadette: I got it.
- Penny: No, no, it’s…
- Bernadette: I got it. Why do you have a history textbook?
- Penny: No, it’s not a big deal. Just taking a class at the Pasadena Community College.
- Bernadette: That’s great. I didn’t know you wanted to go back to school.
- Penny: It’s just one history class. Look, I didn’t finish college, so I thought I would give it a try.
- Amy: Not to mention, your acting career is going south like Sherman. Read about it in your book.
- Bernadette: Why would you be embarrassed to tell us?
- Penny: No, I’m not embarrassed. I just didn’t want anyone to know because I haven’t told Leonard yet.
- Amy: Why wouldn’t you tell Leonard?
- Penny: Because it’s me going back to school, and he’s gonna be all “you can do it,” and “how can I help?” and “I’m so proud of you.” Ugh!
- Bernadette: I just can’t believe you could keep something like that from him.
- Amy: You guys have got to be the weirdest couple I know.
- (There is a long pause of Penny glaring angrily at Amy for five seconds, Amy now nods her head silently)
- Penny: Really? You can’t think of anyone weirder?
- Amy: I can, (she whispers away from Bernadette) but she’s sitting right there.
- (Bernadette stares at Amy harder and says nothing as she is now insulted by what Amy had said).
- Amy: How’d it go with Leonard?
- Penny: I don’t think he’ll be making that mistake again.
- Bernadette: Good.
- Penny: So, I know this goes without saying, but if either of you tell Leonard you helped me rewrite this paper, I will beat you both with a bag of oranges.
- Amy: Understood.
- Bernadette: Got it.
- Penny: Now, ladies, we got a B-minus on this paper. I think if we put our heads together, on the next one we could get an A.
- Bernadette: Uh, but we got you a B-minus on purpose to make it believable.
- Penny: Believable? You saying I’m not smart?
- Bernadette: No, no!
- Amy: You’re smart.
- Penny: That’s better.
- Amy: I feel like I’m in high school again.
- Bernadette: Yeah, doing the prom queen’s homework so she’ll like us.
- Amy: I know; It’s finally working.
- ↑ The TV Critic's Review
- ↑ The Big Bang Theory: “The Extract Obliteration” - TV Club - The A.V. Club
- ↑ Live+7 DVR Ratings: 'Modern Family' Leads Adults 18–49 Ratings and Viewership Gains; '666 Park Ave' Biggest Percentage Gains in Week 6 - Zap2it
- ↑ Top Programs – Total Canada (English) October 29 – November 4, 2012 - BBM Canada
- ↑ BARB via Wikipedia