According to this episode, Principal Skinner has been an intern principal for 20 years.
Continuity: The gym teacher says that Coach Lugash "defected into East Germany." But in the episode "Children of a Lesser Clod," Lugash is said to have escaped from East Germany by cartwheeling over the Berlin Wall.
In the part with the Itchy and Scratchy cartoon, you see Itchy pour the butter on the toast and Scratchy's eyes are no where to be seen but in the next shot, Itchy's takes a bite out of one of Scratchy's eyes.
When Homer is throwing the frisbee to get Bart out of the tree, we see the peices of wood nailed onto the tree for Bart's treehouse, but then moments later they are gone, so that Lisa can use her gymnastics to get to the top.
When Bart is eating (slurping) his soup in the bubble, Homer gets mad and fills Bart's bubble with water. When Homer picks up the bubble, the soup is no where to be seen.
Skinner is the only one to get chocolate cake splattered on him.
One of the girls in Lisa's gymnastics class jumped out the window just as Lisa got there, but about a minute later, the girl that jumped out the window is on the balance beam.
The night that Lisa sneaks out to go to the poetry reading, as Homer walks by the kids rooms saying goodnight, Bart and Lisa's rooms seem to have switched positions.
Skinner's estimated life as listed on the plaque is "1953-2010" making him only 57 when he dies.
Sherri and Terri are participating in the 2nd grade gymnastics class but they're in the 4th grade.
Lisa: (thinking) Wow, I'm actually passing as a college student! And they don't have a Blue's Clue! Whoa, gotta age it up a bit...
Marge: (About Bart) What's wrong with him, doctor? It can't be mange. I just had him dipped!
Homer: I was trying to throw Bart over the roof, and he got stuck in this tree. Marge, where's my pellet gun?
Marge: In the tree!
Lisa: It was a bustling marketplace of ideas!
Marge: Oh, and this kitchen isn't?
Lisa: I share a house with a couple of girls, a couple of guys.
Tina: Guys, huh? Are they cute?
Lisa: Well, Bart is kind of . . . NO!
Agnes: I've got a question. How dare you wear white? I hear what you do at night!
Principal Skinner: Security!
(Two kids drag Agnes off the school grounds.)
Agnes: Get your hands off of me.
Ralph: Look, up there, it's Lisa and she's winning us back!
Ralph: Why do people run from me?
Gym Teacher (about Lugash): He's really tough. He defected INTO East Germany.
Lisa: I know just how you feel. Isolated, alone, cut off from everyone.
Bart: Are you kidding? This little baby has made me more popular than ever.
Lenny: Hey, Bubble boy! Lookin' good!
Carl: Call me!
Willie: Don't let 'em get to you, lass. I'm too good for this place too. Now run home to your shack.
Lisa: I live in a house!
Willie: Well la-di-da, college girl! Well I guess you're too good for me too!
Lisa: Doogie Howser went to college when he was my age.
Homer: Against my wishes!
Kearny: Give me your lunch money.
Wendell: But it's after lunch!
Kearny: It's just an expression. Like, kick your butt could involve no kicking whatsoever.
Homer: (breaks window) Hey, where's my keg?
Lisa: Mom's not going to like that.
Tina: Who's mom?
Lisa: Umm, that's what we call the gay guy who lives with us.
Lugash: For next exercise, put hands on hips, jump out window, and go tell parents to STOP WASTING TIME WITH FAILURE CHILD!!!
Carrie: Aren't you in college?
Lisa: Uh… of course! Where do you think I go baby school?
Ralph: See ya tomorrow, Lisa. We find out what five minus three is!
Lisa: Um… I'm in teacher's aid in a very special class.
Ralph: No Lisa, we're both in…
Lisa: Go! Go! Go!
Marge: I knew it was serious when he said he didn't want ice cream!
Bart: I did want ice cream.
Marge: Well, your father ate it all.
Lisa: (Awaking from a dream) Ich ben ein gymnast!
Homer: Aww, she must have dreamt about Hitler again.
Ms. Hoover: (seeing Lisa's project) Well, it is still the best thing in this class.
(Scene cuts to showing how everyone else in class has a bad project and Ralph is eating his)
Ms. Hoover: A minus!
Lisa: (chuckles) Lisa Simpson, master of the double life. (She falls asleep)
Ralph: You're like my mommy after her box of wine.
Bart: Grampa, will you take me to the hospital?
Grampa: Finally, we're doing something I wanna do.
Bart: Everything seems to sort of shimmer. You won't believe what that sunset looks like to me.
Lisa: That's not a sunset, that's a bird on fire!
Bart: Tomato, to-mah-to.
Principal Skinner: I've been taken down a peg... A whole peg!
Janey: We're gonna roll down this hill.
Lisa: Can I come?
Janey: Are you sure you're not too college for us? (Rolls down)
Milhouse: Yeah, sorry we can't be too college! (Rolls down)
(Ralph stares blankly and rolls down with no comment.)
Bart: Step into my office.
(Lisa steps into the bubble)
Lisa: Ew, Bart!
Bart: Wasn't me.
Bart: Contagious? Cool! I got me some teachers to lick!
Homer: (Singing to the tune of "I Get Knocked Down) I take a whiskey drink;
I take a chocolate drink.
And when I have to pee,
I use the kitchen sink.
I sing the songs that remind me I'm a urinating guy!
Lisa: Who wants to put on a leotard and get screamed at?
Homer: Well, hookers and Spiderman ...
Lugash: You girls were great! Cats back for everyone!
Tina: I had a dog.
Lugash: Is cat now!
It is revealed in this episode that Moleman is 80 years old.
The Itchy and Scratchy episode's production code was DABF06 which is really the production code for an episode of The Simpons entitled "The Bart Wants What it Wants".
Blackboard Joke: None.
Couch Gag: Two teenagers are making out on the couch when the family enters the room.
Man in Cafe: Open your minds for the Coltrane of the quatrain.
He was comparing Robert Pinsky to legendary jazz musician John Coltrane.
Lisa (to herself): I'm passing as a college student, and they don't have a Blue's clue. Oops, gotta age it up.
A quick reference to the children's TV show "Blue's Clues" and its star Blue, the blueberry-spotted dog.
When Lisa begins her switch from elementary school goody-goody to a cool college girl after leaving the school grounds, the "Pink Panther" theme, by Henry Mancini, from the 1963 film (as well as the cartoon series from 1964 to 1980) can be heard playing. When the three boys sneak through the college, a slight imitation of the theme is heard then.
Lisa notices one of the other two girls at Lugash's gym is reading Gravity's Rainbow, which is a novel written by American author Thomas Pynchon. The novel is set in Europe at the end of WWII, and features the creation of the first military ballistic missiles as a main theme. It's also worth noting that Thomas Pynchon has later appeared as himself in a couple of other Simpsons' episodes.
Man In Cafe (testing the microphone) : April is the cruelest month, cruelest month.
"April is the cruelest month" is a line from TS Eliot's poem "The Wasteland."
Nerd 2: "AAAAH, this is the life we chose."
This line is uttered by the other nerd after Milhouse pulls him and Martin off the fence where they have been hung by their wedgies. This line is said by Hymen Roth in the 1974 film "Godfather II.
The Itchy and Scratchy cartoon titled "Butter off Dead" is a reference to the title of the 1985 film Better Off Dead starring John Cusack.
Bart: When nerds are in trouble, I am not slow! For it's spin, spin, spin and away I go!
This is a take-off on the uttered by Underdog, usually when he was going to rescue Sweet Polly Purebred.
Database: I feel like Harriet the Spy!
"Harriet the Spy" is a series of children's books about a young girl who's a detective/spy. This was made into a film in 1996.
Scratchy: I Can't Believe It's Not Scratchy!
When Lisa is watching the Itchy and Scratchy cartoon, there's a butter that says "I Can't Believe It's Not Scratchy!" It obviously refers to the butter, "I Can't Believe It's Not Butter."
Homer: I take a whiskey drink... (etc.)
This is an alternate song to the beat of Chumbawumba's 1997 song "Tubthumpin."
The course at Springfield University where you watch and study "Itchy and Scratchy" cartoons is based on a class in Oxford University where you watch and study episodes of "The Simpsons."
Music: Also Sprach Zarathustra
The music that plays when Lisa falls on the chocolate cake in this episode is the piece cited above. The piece is best known for its use in Stanley Kubrick's "2001: A Space Odyssey."