ACT I
"Oh The Thinks You Can Think"
The Cat, Boy
"Horton Hears a Who"
Cat, Boy, Horton, Bird Girls, Jojo, Jungle Creatures
"Biggest Blame Fool"
Sour Kangaroo, Little Kangaroo, Horton, Wickersham Brothers, Bird Girls, Jungle Creatures, Gertrude, Mayzie, Cat, Thing 1, Thing 2
"Here on Who"
Mayor, Mrs. Mayor, JoJo, Horton, The Whos
"How to Raise a Child"
Mayor, Mrs. Mayor
"Oh The Thinks You Can Think (reprise)"
Jojo, Ensemble
"It's Possible (Pt. 1)"
Jojo, The Cat, Fish
"It's Possible (Pt. 2)"
Jojo, The Cat, Fish
"Alone in the Universe"
Horton, Jojo
"The One Feather Tail of Miss Gertrude McFuzz" / "Amayzing Mayzie"
Gertrude, Mayzie, Bird Girls
"Amayzing Gertrude (Pt. 1)"
Gertrude
"Amayzing Gertrude (Pt.2)"
Gertrude
"Monkey Around" / "Chasing the Whos"
The Wickershams, Sour Kangaroo, The Cat, Horton, Bird Girls, Jungle Citizens, Whos
"Notice Me, Horton"
Gertrude, Horton
"How Lucky You Are"
Mayzie, The Cat
"Mayzie's Exit" / "Horton Sits on the Egg" / "Dilemma" / "Hunters"
Horton, Gertrude, Bird Girls
ACT II
"Egg, Nest, and Tree"
Sour Kangaroo, Horton, Hunters, Bird Girls, Jungle Citizens
"Sold" / "Mayzie in Palm Beach"
Sour Kangaroo, Horton, Bird Girls, Jungle Citizens, Mayzie, The Cat
"Mayzie at the Circus"
Mayzie
"Amayzing Horton"
Mayzie, Horton
"Alone in the Universe" (Reprise 1)"
Horton
