Lehrer identifies this as a 1987 speculative lyric for a proposed Disney Channel reading series that was never produced. A is orderly and B mischievous; their repeated reversals eventually undo some damage as well as causing it. This is the complete scripted lyric, including the spoken exchanges and bracketed stage directions. It is not labeled as a released television song or a recording.
A: I fold the shirt
B: I unfold the shirt
A: I lace the shoes
B: I unlace the shoes
A: I stack the clothes
B: And I unstack them
A: I pack the clothes
B: And I unpack them
It should be clear to anyone:
Anything you can do --- I can un.
A (spoken): Why, that's the most unheard of thing I ever heard of!
B (spoken): I think you're getting the idea.
A: I wrap the box
B: I unwrap the box
A: I tie the string
B: I untie the string
A: [trying to keep B away] I lock the door [between them]
B: And I unlock it
A: I block the door
B: And I unblock it
Undoing things is lots of fun -
Anything you can do --- I can un.
A: I button my shirt
B: I unbutton your shirt [it falls off]
A: I buckle my belt
B: I unbuckle your belt [pants fall down]
A: [getting angry] I dress again
B: Well, just to impress you
I undress you. [A's clothes fall off, down to underwear. A sneezes.]
Bless you!
A (spoken): Why, you unspeakable, unbelievable, unscrupulous, unmitigated. ...
B (spoken): Don't forget “unfair”!
A: I comb my hair
B: I uncomb your hair [it's a mess]
A: I blow my nose [blows]
B: I unblow your nose [A inhales]
A: Oh, yukk!
I make the bed
B: And I unmake it
A: [trying to stop B, falls on bed -- it collapses] Oops! I break the bed
B: And I unbreak it
A: [surprised that B has actually done something helpful] Why, thank you!
B: You're unwelcome --it was unintentional
BOTH: "Un" can undo whatever you've (I've) done
Anything you (I) can do, I (you) can un!