The detective talking to Lip:
D: “Phillip Gallagher … no relation to our favorite
overnight guest Frank I hope?
L: “Son.”
D: “Your Frank’s kid and this is your first felony bust?
Getting a little late start for a L: Gallagher aren’t you?”
L: “Slow study, I guess.”
Steve and his boss:
Boss: “What happened to you?”
Steve: “Pick-up hockey game.”
Boss: “What were you? The puck?”
Ethel siding with V who said Lip and Ian need a legit lawyer:
“She’s right, my husband’s public defender never even met
Clyde before his arraignment then suggested he plead guilty to child
molestation and sexual abuse.”
(Awkward silence from the room)
Debs returns to the Lischman's:
Mrs. L: “More cookies to sell?”
D: “Is Jimmy here?”
Mrs. L: “No, he’s back at school in Michigan.”
D: “No, he’s living 96 blocks away on the South Side, dating my
sister, stealing cars, and going by the name of Steve.”
Fiona and Carl:
F: “Carl go help Veronica with dinner”
C: “I helped with breakfast”
F: “You pulled out a cereal bowl.”
Lip and Fiona:
L: “Hey, Fiona … I’m gay.”
F: “I know.”
L: “I should have told you a long time ago, I don’t know why
I didn’t.”
F: “You’re still on my shit list.”
Another Frank rant:
“Hannah Montana … those oversexed kids on Glee? Think
they’re selling good wholesome all-American fun? Hell no – flesh and underage
temptation! You can look, but oh no, you can’t touch!”
Steve offering Tony the house:
T: “You paid for the house in cash?”
S: “It’s a shitty neighborhood, I could’ve bought two”
T: “How many cars have you stolen?”
Carl and Fiona:
C: “You figure out what you’re going to do to them yet?”
F: “Huh?”
C: “Punishment? Ground them for a year?”
F: “Nothing, I’m not their mother.”
C: “So, I can steal a car and nothing will happen to me?”
F: “You steal a car and I’ll smother you in your sleep.”
Frank trying to weasel some cash out of Sheila:
F: “I know a guy who sells cars, why don’t you give me the
money, I’ll find her something nice.”
S: “Maybe a Volvo? I heard those are real safe…”
Steve to Fiona, on why he can’t just turn himself in:
“Look at me … I can’t go to jail, I might as well wear
heals.”
Steve’s final pitch:
“Come with me Fiona. How long is it going to be about them
and not about you? When are you finally going to do something for yourself? …
Liam’s two – sixteen more years until he’s out of the house … you’ll be what?
37? 38? And who says Frank’s done dumping babies in your lap to raise? You
deserve a life of your own.”
Lip afterwards:
“He’s right … you should go Fiona, you’ve done more than
enough – we’ll be alright.”
Frank:
“It’s like the moon orbiting the Earth. These things show up
and you know you shouldn’t, but then you do and then you don’t know what to do
… but we can’t hold it against her, she’s young and carefree. I mean, we’re the
victims here, you and me.”
He continues:
“The bible says, it is blessed to forgive son, and that
forgiveness is the first step on the stairway to heaven.”
L: “Slow study, I guess.”
F: “Carl go help Veronica with dinner”
C: “You figure out what you’re going to do to them yet?”
Much of the finale revolves around the aftermath of that
incident. Karen sends the video off to Eddie and everyone else with the
misleading title, “Father of the Year.” Soon after, everyone on the South Side
had seen the video from Eddie to his co-workers to other neighbors. In fact,
Lip was one of the last to hear of it, but when he found out he was none too
happy, this was of course after Karen broke things off earlier in the episode –
now he knew why. To make things worse, around the same time, Lip came to the
realization that he was actually falling in love with Karen – something he
wasn’t sure what to make of. There was more fallout from the video as Eddie
chased Frank around, before ultimately committing suicide in the season’s
lowest moment. While Frank didn’t try to kill himself, Lip tried to kill him,
ironically, with a car he had stolen. Lip didn’t run down Frank, instead
crashing the car, but he got a few good jabs at his father before Kev stepped
in to break things up. 
Steve of course, wasn’t going to flee the country without
returning to the Gallagher house first and dropping off a ticket for Fiona to
join him. Fiona, you can see is feeling conflicted and much like Lip’s realization, Fiona realizes that she’s falling in love also.
After Steve leaves, one of the most poignant moments of the entire season takes
place when Lip walks into the room in the dead of night and tells Fiona that
it’s alright and that she should go off with Steve. V tells her the same thing
the next day, more in typical V fashion, not quite in the same heartfelt way
Lip delivered his message. 
D: “Then it’s even weirder...”
Carl staring at Frank:
After last week’s bombshell that Frank is not Ian’s
biological father, Lip and Ian (Mostly Lip), made it their mission to find out
which of Frank’s three brothers is Ian’s actual father. Not surprisingly, the
Gallagher’s don’t really do family reunions (add it to the list) so the boys
have never met any of their uncles. In fact, in order to find out their names
Ian and Lip had to go visit Grandma. Silly me, I was thinking Ian and Lip were
going to go over their Grandmother’s little cottage house, where she would have
warm cookies waiting on the table. I should have known better, turns out
Grandma Gallagher is in the clinker, and has been since her meth lab exploded. 
S: “You’ve got a drivers license, right?”