Nearly 50 years before Jimmy Fallon and The Roots performed with pop stars and kazoos for The Tonight Show’s Classroom Instruments bit, or James Corden strapped chart-topping singers into the passenger seat for Carpool Karaoke, Sesame Street invited celebrity guests to perform original songs and musical parodies in the service of educating preschoolers while entertaining their parents.

In many ways, Sesame was the proto-viral show — and its all-ages public television singalongs were the pre-Internet equivalent of viral music videos, effortlessly humanizing such artists as Johnny Cash, Billy Joel and Nina Simone, much like Fallon’s and Corden’s segments do with their guests.

This month, Sesame Street’s 46th season rolls out on PBS — its first since Sesame Workshop, the show’s educational production nonprofit, announced a five-year deal with HBO. (New episodes premiere on the pay-cable channel and then, after a nine-month window, re-air on PBS.) The partnership’s symbolic gentrification initially caused an online hullabaloo: A public television series founded expressly to teach inner-city preschoolers the ABCs would now premiere on premium cable. And in July, another controversy arose when veteran cast member Bob McGrath told a fan-convention audience that he, Gordon and Luis (respectively, Roscoe Orman and Emilio Delgado) were “graciously let go” from the show. That wasn’t exactly true — and Workshop CEO Jeff Dunn quickly apologized for the “misunderstandings” in a statement, saying the three were still “a key part of the Sesame family.” (Season 47 airs on HBO in January; special guests will include James Corden, Sia, Jason Derulo, Tori Kelly and Little Big Town.)

Public reaction to these changes was a sign of just how much Sesame Street is revered by both boomers and millennials, but the show has always evolved with the times. From its November 1969 debut, Sesame Street sought to reflect the sensibilities of broader American culture: The show's hour-long premiere included a six-minute Simon & Garfunkel-esque tribute to milk's suppliers called “Hey Cow” and a psych-jazz composition featuring the voice of Grace Slick, who’d already notched two Billboard 200 Top 10s with Jefferson Airplane, counting from one to 10. Along with a neighborly cast of adults and Muppets — puppets created by a young visionary named Jim Henson — music was core to the show’s identity, producing more than 2000 original songs and more than 140 LPs over the years.

Led by founding musical director Joe Raposo, Sesame Street introduced new standards to the American songbook, including its theme, “Can You Tell Me How to Get to Sesame Street?”; the title song for the segment One of These Things (Is Not Like the Others); Kermit the Frog’s signature ballad “Bein’ Green”; and Muppet Ernie’s buoyant ditty “Rubber Duckie,” a 1970 Billboard Hot 100 top 20 hit. “Prince was the only person besides Raposo who could make simple melodies so universal,” says Questlove, who wrote a song for Pharrell Williams’ appearance in 2016. (Raposo died in 1989.)

Sesame Street’s musical guests, who are wrangled by an in-house booker, have always reflected the pop charts, from Stevie Wonder in 1973 to Gwen Stefani and Nick Jonas in 2016. Over the years, Tony Bennett has serenaded Oscar the Grouch’s pet worm, Slimey, into space, Little Richard banged his piano keys from a soapy bathtub and Destiny’s Child harmonized about a silly walk. Today, the show’s current musical director, Bill Sherman, is tied to the current zeitgeist as well: A longtime colleague of Hamilton creator Lin-Manuel Miranda, Sherman, a 35-year-old father of two, produced the musical’s original cast recording. “What do we all have in common?” says Sherman, one of more than 25 past and present principals and guests who talked to Billboard about the series’ musical history. “ We all pay taxes and we all grew up on Sesame Street.”

Christopher Cerf, editor-in-chief of books, records, and toys division?, Children’s Television Workshop; (1970-1979); composer-songwriter (1973-1999)

Joe Raposo, the first musical director, decided very early there would not be one music style. We wanted kids to hear all different music: R&B, opera, show tunes, folk, world music.

Dr. Rosemarie Truglio, senior vp, curriculum and content for Sesame Workshop

From the beginning, Sesame was innovative for using music to teach curriculum goals. “C Is for Cookie"? That's a literacy moment.

Caroll Spinney, Big Bird; Oscar The Grouch

I got the job when I was 35. I didn’t think of myself as a singer, but Jim Henson expected I would sing, so I didn’t get all fussy about it. I can carry a tune.

Sonia Manzano, Maria (1971-2015)

Everybody had to sing on the show.

Bob McGrath, Bob

As soon as I started singing on Sesame Street, I got calls from symphonies to do family pops concerts. It's a great gig when they say, “Please welcome Big Bird's best buddy, Bob!” and you get a standing ovation from the introduction.

Manzano

When I first heard “Rubber Duckie” [written by head writer Jeff Moss], I could see a nightclub singer doing that song. It had double-entendres. It wasn’t treacly.

Spinney

Pete Seeger was the first musical guest. The second was the “American Pie” guy, Don McLean. Pete Seeger was so fascinated that he stopped singing, gazed up and said, “I’m working with Big Bird! I can’t believe it.” Big Bird can be a distraction.

Truglio

Sesame Street was a breakthrough in designing what we call a ‘co-viewing experience': Children learn best when adults are co-engaged — and celebrities helped bring in those adults.

Manzano

Stevie Wonder came on in 1973 and did “Superstition” [with Grover]. That was terrific. Old people, young, white, black — everybody was grooving.

John Carter Cash, Producer; Son of Johnny Cash

When I was a boy in the '70s, I watched Sesame Street every day, twice a day. The first time my dad was on Sesame Street [in 1973], I was 3 and very confused on set when Big Bird took off his head. Then I looked up and saw Mr. Snuffleupagus hanging from the ceiling. It was shocking.

Ruth Pointer, The Pointer Sisters

When we got to the studio and they presented us with “Pinball Number Count” [the theme to a recurring counting segment], we looked at each other: “Are you kidding?” That song was really difficult! Gospel, jazz — we had to sing it in parts. I don’t know if we would have been prepared if we hadn’t grown up singing in the church.

Manzano

When Lena Horne was on [in 1976], she sang "Bein’ Green" with Kermit. I remember being taken aback: Jim Henson played Kermit so dramatically — so sadly — that a puppet really complimented her profundity.

Norman Stiles, Writer, head writer, lyricist (1970-1999)

In 1978 we did Sesame Street Fever, a disco LP in response to Saturday Night Fever. The cover is Grover in a white John Travolta suit.

Spinney

I sang with a Bee Gee [on that] — one of the handsomer ones [Robin Gibb].

Cerf

If we couldn’t get a celebrity, the Muppets’ [creators] would build a copy of them. They made The Beetles, a band of puppets with antennae.

Spinney

There was a lawsuit because [the 1979 spoof] “Letter B” was too close to “Let It Be.”

Cerf

One day I got a letter with a $5 million lawsuit by way of Northern Songs, The Beatles’ publisher. The Workshop was quite nervous about it — and understandably so. We also had [1982’s] “Hey Food,” a parody of “Hey Jude,” in which Cookie Monster sang. Eventually, Michael Jackson bought the catalog and settled the case for $50. Somewhere, I have that $50 canceled check with Michael’s endorsement.

Spinney

When I did [the 1985 film] Follow That Bird, Waylon Jennings played a turkey-truck driver. Big Bird was hitchhiking, trying to get back to Sesame Street, and Waylon picks him up. We got to be great friends because we spent two days in this truck. We sang “Ain’t No Road Too Long.”

Itzhak Perlman, Violinist, Recurring '80s guest

I was on more times than I can remember: There was a classical Muppet, Placido Flamingo, I performed with; I did “Put Down the Duckie” [a follow-up to “Rubber Duckie” that featured verses sung by subsequent celebrity guests]. Now at my concerts, adults backstage tell me, “I saw you on Sesame Street,” and I say, “I must really be old.”

Manzano

A special moment for me was when Celia Cruz, the great Cuban singer, came on the show. She participated in "Put Down The Duckie" and then sang one of her hits. I thought, "My goodness, we actually have real — not hokey — Latin music.”

Cerf

I was a Bruce Springsteen freak, and I was assigned to write a song about simple addition, so “Born to Add” occurred to me. The album it inspired [Born to Add: The Great Rock & Roll From Sesame Street] got nominated for a Grammy in 1984, the year that Michael Jackson was going to break the record for most Grammys in one night. He was nominated [for E.T. The Extra-Terrestrial] in the kids’ category, so it was televised. I sat front row next to Cyndi Lauper. Guess what? I lost. Michael Jackson edged me out.

Stiles

One of my favorite guests was John Candy. He did a bit that Chris Cerf and I wrote for his Polish polka-playing clarinet player character [SCTV's Yosh Shmenge].

Cerf

We used to have lunch at a little restaurant called the Isle of Capri. We would have a glass of wine, toss around lyrics, and have a generally fabulous time. One day Norm said, "John Candy's coming on. Why don't we do an ‘alphabet polka’?" I said, "Oh, good: Yosh Shmenge! Let's figure out what we're going to write." Norm said, "I wrote it just now: ‘A-B-C-and-D / E-F-and how 'bout G? / Hey! Do the alphabet polkaaaaaa!’"

Stiles

So John Candy did it. Slimey the Worm played the tuba; his whole face was inside the mouthpiece. But we had to cut it from the show after it aired. A Polish-American society thought it was making fun of Polish people.

Cerf

I was on vacation [in 1986] with Henry Beard, who started National Lampoon. His stepdaughter, who'd grown up on Sesame Street, was there and said, “There’s a [style of] reggae music called ‘rubber-duck reggae.’ You should do that on Sesame Street.” When I got back, Norm and I wrote “Do De Rubber Duck,” a song about hygiene. We wrote the scene so all the Muppet characters gradually get in Ernie’s bathtub, except Bert, who can't get in the room. In recent years, it was decided this was a homosexual thing. I believe they took it off.

Sarah Durkee, Songwriter (1985-1999)

One of the first things I co-wrote was “Rebel L,” a [1988] Billy Idol parody that was my first lesson in Sesame’s strict curriculum standards. A lyric read “Lean a little lower” and we had the character [Billy Idle] leaning out a window. Someone in research said, “What are you thinking? Leaning out a window?”

Cerf

The very strict rule was, by all means, put adult jokes in, but if the bit depended upon something a kid might not understand, we couldn’t do it.

McGrath

I sang “The People in Your Neighborhood” with Barbara Walters, Martina Navratilova and Ralph Nader [on a 1988 PBS special]. For Ralph’s part, we sang: “A consumer advocate’s/A person in your neighborhood.”

Spinney

One time, I was singing with Ray Charles and his producer said, "How’s it feel to sing with Ray Charles again?” I said, “I did this before?” I’d done so many [duets] I couldn’t remember. I wish I had a list of everybody I've performed with — it’s probably a good 40 people.

McGrath

I often get asked who my favorite guests were. I’d have to flip a coin: Getting a hug from [Mister Rogers’ Neighborhood host] Fred Rogers or a peck on the cheek from Beyoncé — I'll let you figure out which one I enjoyed more.

Spinney

We’ve had a few bombs. They weren't asked back.

Manzano

We didn’t have bad singers. Maybe some distracted ones. Some weren't sure where they were, but I'm not going to tell you who they were.

Sherman

Certain artists can’t be on the show because they have relationships to drugs or other things you can’t associate with Sesame Street. Eminem, whom I love, can’t be on Sesame Street.

Matt Vogel, Muppet Captain, Count von Count

I’ve always thought Barenaked Ladies would be good on the show, but their name is an obstacle.

Spinney

We did a Christmas special in 1978 and Oscar sang “I Hate Christmas.” It was a funny list of Oscar’s hates. Then Michael Bublé had a [2011] Christmas special and said he’d always wanted to do “I Hate Christmas.” I was all excited about singing that again, but was then told I couldn't sing a song against Christmas. I argued a little: “Oscar is all upset because he can't sing his song!” I was told [by Sesame Workshop], “It's not politically correct.” I said, "The hell with politically correct." So we instead did, “Have Yourself a Merry Little Christmas.” But it was more like (in Oscar’s voice): “Have yourself a rotten little Christmas.”

Johnny Rzeznik, Goo Goo Dolls (2000 Guest)

I always watched it growing up and the characters on this television show were as real as my siblings. Seeing the set, I got goosebumps. The steps, Mr. Hooper’s Store, Oscar’s trash can. After 30 seconds, I was having a conversation with Elmo. The guy with his hand up the puppet’s ass was invisible.

Sherman

One Direction couldn’t believe they were meeting Big Bird. Harry [Styles] was like, “I used to have a Big Bird doll and I loved it.”

Norah Jones (2005 Guest)

I remember putting my arm around Elmo and feeling his heartbeat. It was so weird. I was like, “He is real!”

Feist (2008 Guest)

I was so fascinated with the Muppeteers — their coordination is the most subtle ballet of all time. At one point, I was in the recording booth on set and, in a very Muppet-y moment, all these little Muppet faces rose up in the glass and I was 7 years old again. It was like I’d walked into a TV set.

Tim Nordwind, OK Go (2012 Guest)

I listened to Sesame Street albums all the time on my Fisher-Price record player. I loved all the songs, except anything by The Count [von Count]. To this day, if I hear his “Mwha-ha-ha-ha,” I get a twinge of fear.

Jason Derulo (Upcoming 2017 Guest)

I showed The Muppets dance moves. They were literally, like, live little people.

Brown Johnson, Executive evp and creative director, Sesame Workshop

The most popular videos on Sesame Studios [the Workshop’s YouTube channel] are all songs.

Sherman

My first viral video was the second song I wrote with [songwriter, Hamilton actor] Chris Jackson, “What I Am” for Will.i.am. Will reworked the tune and it went viral. I feel like I’ve been trying to live up to that ever since.

Joey Mazzarino, Writer, director, head writer, Muppeteer (1990-2015)

My four-year-old daughter was having issues with her hair: She’s African-American; my wife is white with long, blonde hair; and my daughter suddenly wanted straight, “princess” hair. We thought this was unique to our family, then Chris Rock's [2009] movie Good Hair came out and I realized it was a broader issue. I wanted my daughter to be proud of her hair, so I wrote “I Love My Hair” quickly with Chris Jackson. Right after the song aired, a 53-year-old woman working for a state senator called to say she’d cried when she saw it. Then it went viral with not only kids, but adults. I'd been on the show for 20 years, but having that experience with the web made me realize we still had a much broader impact than I'd even realized.

India Arie (2005 Guest)

Me singing with Elmo has, what, 123 million views? It's crazy. That is my most-watched anything. People talk to me about it all the time. Everywhere. I sang the national anthem at a Seattle Seahawks playoff game in 2015, and as I was coming off the field and the guy they call Beast Mode, Marshawn Lynch, shook my hand and said, "You are so fine." I was like, "Thank you." Then another player walked up to me — a very tall white man on the Carolina [Panthers] team. I was like, What is he about to say? He said, “My son loves you.” I said, “Your son?” He said, “He watches your Elmo video multiple times a day.”

Feist

I'm usually approached at airports: Parents with children come up, so excited, and without exception, the kids just stare blankly at me — they were looking at the Muppets, not me. It's the parents who associate the song with a person.

Scott Hoying, Pentatonix (2014 Guest)

I grew up watching Sesame with my sisters; I was a huge Big Bird fan because he was tall and awkward like me. Now, all the time, people say, “My kids watch your Sesame Street performance every day.” We’re asked about it so much, I checked YouTube and our video has nearly 40 million views. I had no idea.

Sherman

I met Questlove while co-producing the Hamilton record, and he, to this day, still watches Sesame Street. When Pharrell came on and did “B Is for Books,” Questlove wrote it. When we made the Broadway cast recording, [we] talked about Cookie Monster the whole time.

Questlove, The Roots

The only two shows my parents let me watch growing up were Soul Train and Sesame Street. It’s one of the pop-culture references I use every day, much to the chagrin of anyone born after 1981. I still go to the Sesame Street Wiki and watch clips on YouTube. Bill was shocked at that. He’s like, “Wait, you’re still actively watching it as a 45-year-old man? That’s weird.” No, it’s not! That’s my childhood.

Sherman

?Sesame Street’s musical styles have changed with the times. Now we use a lot of synth-pop, but not every character fits that. Grover's vibe is soul. Elmo can do anything. Big Bird is more old-school, like The Beatles. Oscar is the blues. Abby [Cadabby] is super pop because she’s the newest. Cookie Monster is goofy. His songs are always rants. Bert and Ernie are showy, cabaret.

Truglio

We keep Sesame Street current for today’s children.

Johnson

We’re doing fewer parodies now because kids weren’t necessarily getting as much as they could from straight storytelling. But they work incredibly well on social media, so we’ve done parodies for Icona Pop, “Me Want It (But Me Wait),” and Carly Rae Jepsen, “Share It Maybe” [for the YouTube channel].

Sherman

For me, it’s an interesting dance: How do you continue to pay homage to “The People in Your Neighborhood” or “Rubber Duckie” but add something to define Sesame now? I’m always pushing my guys: “Let’s write the new ‘Bein’ Green’ or the new ‘C Is For Cookie.’ ”

Aloe Blacc (2016 Guest)

When somebody tries to be extra different today, “One of These Things (Is Not Like the Others)” comes to mind. Like when Kanye West first started wearing skirts? [sings] “One of these things/Is doing his own thing.”

Nordwind

Sesame Street is such an iconic memory of my youth. To be on the other side was more than a dream come true — it was like an alternate reality come true.

Arie

I don’t remember not watching Sesame Street. It was a world in which no one was excluded. It wasn’t black or white. It’s black and white and Hispanic and blue and purple and boys and girls and music and kids and adults. It’s everything.

A version of this article originally appeared in the Oct. 8 issue of Billboard.