Online, news of Stephen Hillenburg’s death was greeted with SpongeBob SquarePants memes and mournful quotations from his most famous creation. (“Today, mayonnaise is an instrument.”) In the Slate offices, it was met with equal amounts of sadness and nostalgia, especially within a particular age range. SpongeBob has been on the air since 1999, meaning that Hillenburg’s undersea, anthropomorphic comedy has made its mark on countless young viewers, many of whom have now grown up. Slate recruited its team of young millennials, many of whom watched SpongeBob in the late ’90s and early 2000s, to identify the most essential episodes from that early period—and to articulate what it is about SpongeBob that has endured for so long. Here are their picks.

Band Geeks

“Band Geeks” is one of those perfect episodes of television that lingers long beyond your first or fifth or 75th viewing—not least because it introduced me to the absolute banger that is David Glen Eisley’s “Sweet Victory.” I’m not going to say that the episode singlehandedly convinced me to join a marching band, but I will say I was sorely disappointed when I figured out that we had no electric guitar in the ranks. “Band Geeks” typifies so much of what made SpongeBob SquarePants iconic: storylines that got you invested within a few minutes, an unexpectedly catchy bop, and humor that came at no one else’s expense. It’s to SpongeBob’s—and Stephen Hillenburg’s—credit that despite my parents general distaste for all the programming me and my brothers watched, they still can’t help but hum “Sweet Victory” whenever it comes on. —Rachelle Hampton

Sailor Mouth

“Sailor Mouth” has been my favorite episode of SpongeBob for 15 years. For the uninitiated, it’s the episode where SpongeBob and Patrick learn to curse from reading graffiti written on the back of a dumpster. Their first encounter with “salty language” thrills them, and the audience is left having to guess at what they’re saying because the word is censored with a dolphin shriek.

The day after I first saw the episode, I was recounting it for a friend at lunch and trying to imitate SpongeBob’s voice, to no avail. But I realized I had the perfect squeak/screech in my tween-aged voice to nail the dolphin sound. The kids at my lunch table laughed so loudly, and for all of three minutes I felt relieved that I made people laugh because I did something funny and not because I had embarrassed myself. My voice has obviously changed since the fifth grade, so I can’t make the dolphin noise as much as I used to, but every so often I go looking on YouTube for “Sailor Mouth” just to relive that moment. —Aria Velasquez

Chocolate With Nuts

There are ridiculous lines of SpongeBob dialogue that will be ingrained in my brain forever, eliciting almost Pavlovian responses in many millennials. “Chocolate With Nuts” belongs in the canon of quotable episodes for many reasons, but one rises, loudly, above the rest. Does “CHOCOLATE!!!!!!!!” mean anything to you? —Danielle Hewitt

Graveyard Shift

I don’t know if I’ve ever seen SpongeBob characters’ improbable physicality put to better use than in “Graveyard Shift.” Repulsive yet absorbing moments abound: when SpongeBob bites his nails down to the point where he is repeatedly gobbling and re-growing his arms; when his pupils form mouths and start to scream; when Squidward’s nonexistent hair suddenly grows out, individual strands squiggling in a moment of ultimate terror. The dialogue in this episode is likewise brilliant throughout, from the tale of the Hash-Slinging Slasher (“Then he got hit by a bus! And then, at his funeral … they fired him!”) to SpongeBob finding joy in working “at niiiiiiiiiight” (providing me with a sly verbal add-on I still use embarrassingly often).

In less than 10 minutes, “Graveyard Shift” takes the most surreal elements of the SpongeBob SquarePants universe to bizarre extremes and blends them together seamlessly. Name another TV show that could make an arbitrary Nosferatu cutout cameo work so well. —Nitish Pahwa

Krusty Krab Training Video

One of my strongest memories of the pre-streaming era is of watching “Krusty Krab Training Video” and waiting, desperately and without any concept of TV listings, for Nickelodeon to air it again. Told entirely in the form of a welcome-aboard employee film, “Krusty Krab Training Video” was, I think, the first genre-breaking sitcom episode I ever saw. This segment, and many other SpongeBob episodes, taught me to love weird comedy. It also taught me the timeless wisdom of P.O.O.P. (People Order Our Patties). —Madeline Kaplan

F.U.N.

An episode about Plankton trying to steal a Krabby Patty would be pretty standard fare if it weren’t for the instantly classic “F.U.N. Song.” While trying to befriend Plankton, SpongeBob is forced to explain fun, a slippery concept that’s hard to define, so he sings a gleeful little acrostic that gets closer to the feeling than any dry definition could. Every time I hear the word, I can’t help but mentally queue up the opening line, “F is for friends who do stuff together … ”

The best SpongeBob episodes live in that space between what adults enjoy and what kids enjoy. “F.U.N. Song” is a perfect example: It embraces the default setting of SpongeBob’s unabashedly innocent optimism while offering a playful analysis of something we all experience but struggle to articulate. —Daniel Schroeder

The Algae’s Always Greener

In this episode, Plankton makes a wish and switches lives with Mr. Krabs—with the kind of results you’d expect. It’s one of the best “SpongeBob is for kids, but SpongeBob is for adults” episodes, in my opinion, because it reads like a completely different episode depending on your age. Kids spend the episode marveling at Plankton’s inability to mimic Mr. Krabs’ life, while also learning about some of the truly crazy minutia of his days. Adults wonder just how poorly this could go before the problem of the week is solved. It was the episode that made me realize animated shows can be for adults, too, without being salacious or explicit. (But don’t talk to me about “Mid-Life Crustacean.”) —Dawnthea Price

Bubble Buddy

I think about “Bubble Buddy” more than any other SpongeBob episode. It’s funny, but not the funniest one they made. It’s no “Band Geeks.” It still has me giggling, 18 years later, at “Happy Leif Erikson Day! Hinga Dinga Dergen,” and for pretty much the same reasons. But “Bubble Buddy” is still on my mind because it taught me some heavy stuff when I was young.

When I think of “Bubble Buddy,” I think of myself as a kid learning how to contextualize other people’s actions around the emotions that led them there. Some of the people in the episode only wanted to pop Bubble Buddy because he made them wait in a long line for the bathroom. If that happened to me at a bar, sure, I’d be pretty peeved, but I remember being appalled by what they wanted to take away from SpongeBob just because they had to hold it longer than they wanted. SpongeBob really only has two friends, and he was lonely enough to invent stuff to do and someone to do stuff with. These fish didn’t know that, but it made me think twice about what was going on behind the scenes with people who did stuff that annoyed me. Still does. —Taylor Palmer

The Wet Painters

When I was in elementary school, there was a kid in my class—we’ll call him “Dave”—who would recite entire episodes of SpongeBob word for word. Some kids made fun of him for it, but I remember always being secretly kind of impressed. One of his favorites was “The Wet Painters,” a masterclass in comedic escalation as SpongeBob and Patrick struggle to paint Mr. Krabs’ house. He even nailed all the accents. I’m willing to bet that wherever Dave is now, he still knows every line. —Marissa Martinelli