Big Bird: I have a little song. It isn't very long. (missing lines) (Scene changes to show Bob, wearing an old-fashioned boy's costume with straw hat.) Bob (speaking): Jack and Jill went up the hill to fetch a pail of water. (A lot of water splashes on him.) (Scene changes to show Bob in ordinary outfit, at Oscar's can.) Bob (singing): You go to visit Oscar. You knock upon his can. (Knocks, lid opens and someone says:) Unidentified voice (speaking): Oscar isn't in! (Scene changes to Maria and a human baker.) Maria (singing): You go to see a baker. He's making custard pies. You ask if you can have one, and the baker yells: Baker (holds up a pie): Surprise! (Ready to throw it in her face) Maria (holds up another pie and throws it in his face first): Surprise! Chorus: Surprise, surprise, surprise! (Scene changes to show Bob, wearing Jack and Jill costume.) Bob (speaking): Mary had a little lamb. Its fleece was white as snow. (A bunch of snow dumps on him.) (Scene changes to someone who looks out window and sees Grover hanging from a pole.) Grover: I don't know how I got here. (missing lines) I'm in for a ... (loses his grip and yells as he falls) SURPRIIIIIISSSSSSEEEEE! (Scene changes to show Big Bird, sadly walking down Sesame Street.) Big Bird (singing): Today it is your birthday, you're feeling kind of rotten, Seems all your friends and relatives - they somehow have forgotten, You're feeling sad and lonely when, right before your eyes, All your friends and relatives jump out and yell SURPRISE! Maria: We knew it was your birthday. Mister Hooper (holding up a sweater): I hope this is your size. (I don't know the rest, but I'm pretty sure it ends with Surprise!)
https://primoaccordo.net/sesame-street/surprise.htm