Clockwise from top: “High School Musical,” “Johnny Tsunami” and “Zenon: Girl of the 21st Century.” (Disney via Alarmy; Everett Collection; Disney Channel via Alarmy)

From "Snow White" to "Frozen," there's a Disney classic that brings you back to your childhood. But for those of us who were born in the last 30 years or so, a different kind of Mouse House film helped shape our adolescence: Disney Channel Original Movies.

Since debuting with the Diane Keaton-starring "Northern Lights" on Aug. 23, 1997, this series of made-for-TV films has been usually digestible, often cheesy, sometimes awful, and always a delightful way to escape reality for a little bit.

To celebrate its 100th DCOM ("Adventures in Babysitting," a remake of the 1987 movie), the channel is showing a Memorial Day weekend marathon of fifty-one movies, while the other 48 will play over the course of June, leading up to the debut of the newest film on June 24.

We've found that eight key elements tend to show up over and over in Disney Channel Original Movies. So stroll down memory lane with us while we look at what makes up an old favorite.

Be a launchpad for a future bankable movie star

Before they were taking on increasingly random art projects or appearing shirtless in every film, Shia LaBeouf and Zac Efron were just handsome cogs in the good ol' Disney machine. LaBeouf was the main character on the "Even Stevens" series and took on a serious role as a mentally challenged twin in the DCOM "Tru Confessions," while Efron took the "High School Musical" trilogy all the way to actual cinemas.

But there are a handful of other DCOM actors who, despite not starring in a "Transformers" flick, have still done fairly well for themselves. Kirsten Storms, better known as Zenon, has been on "General Hospital" for more than a decade. "Kim Possible's" Christy Carlson Romano and HSM's Corbin Bleu have both been in multiple Broadway shows. Hilary Duff is still famous for playing Lizzie McGuire because we've never forgotten how bad "Cadet Kelly" was. And Raven-Symoné of "Cheetah Girls" and "Zenon" fame is… well, we all know what Raven's been up to.

And even though they're not technically DCOMs, the Justin Timberlake-starring "Model Behavior," Tyra Banks and Lindsay Lohan vehicle "Life-Size," and Katherine Heigl's "Wish Upon A Star" had eventual airings on the Disney Channel that helped either solidify or launch their stardom.

Related DCOMs: Efron starred in "High School Musical" and "High School Musical 2"; LaBeouf made his mark in "The Even Stevens Movie" and "Tru Confessions"; Storms changed childhoods in all three "Zenon" films ("Girl of the 21st Century," "Zenon the Zequel" and "Zenon: Z3"), "Johnny Tsunami" and both "Kim Possible" animated TV movies; Raven was in two "Cheetah Girls" movies, two "Kim Possible" movies and two "Zenons"; Duff played the spacey "Cadet Kelly"; and Romano was sooo the drama as Duff's "Kelly" foe, Kim Possible and Ren Stevens.

If it's a movie so nice, make it twice (or thrice)

By our count, at least 21 of the 100 DCOMs are not very "original": 13 are sequels and eight are based on Disney Channel series. The nostalgia train isn't stopping anytime soon, with"Life-Size 2," "Descendants 2" and "High School Musical 4" apparently all in the works.

Related DCOMS: For sequels, there's "Kim Possible Movie: So the Drama"; "High School Musical 2"; "The Cheetah Girls 2"; "The Cheetah Girls: One World"; "Zenon the Zequel"; "Zenon: Z3"; "Halloween II: Kalabar's Revenge"; "Halloweentown High"; "Return to Halloweentown"; "Twitches Too"; "Camp Rock 2: The Final Jam"; "Teen Beach 2"; and "Johnny Kapahala: Back on Board." For series jumpoffs, there's "Jett Jackson: The Movie"; "The Even Stevens Movie"; both "Kim Possible" animated films; "The Proud Family Movie"; "Wizards of Waverly Place: The Movie"; "The Suite Life Movie"; "Phineas and Ferb the Movie: Across the 2nd Dimension"; and "Good Luck Charlie, It's Christmas!"

If you have an actor that can even remotely carry a tune, it's a musical

DCOMs are the closest thing we have to classic musicals. Intricate, random group dance numbers? Check. Singing your feelings instead of fighting? Check. A ridiculous plot that comes second to the catchy tunes? Check and check. Though legitimate, modern pop stars have used DCOMs as a stepping stone — Demi Lovato, Selena Gomez, Joe Jonas and Miley Cyrus among them — not all the tune-filled flicks are winners. ("Stuck in the Suburbs" or "Pixel Perfect," anyone?) But it would be hard for anyone to deny the impact that musical DCOMs have had on pop culture: Several of the original movies' soundtracks have landed on (or topped) the Billboard 200 chart, and "High School Musical 3: Senior Year," which debuted in theaters after the first two films performed phenomenally on television, opened to No. 1 at the U.S. box office and grossed over a quarter-billion dollars worldwide.

And life wouldn't be the same without this unforgettable moment from Zac Efron in "High School Musical 2."

Related DCOMs: "The Cheetah Girls"; "Pixel Perfect"; "Stuck in the Suburbs"; "High School Musical"; "The Cheetah Girls 2"; "High School Musical 2"; "Camp Rock"; "The Cheetah Girls: One World"; "Camp Rock 2: The Final Jam"; "Teen Beach Movie"; and "Teen Beach 2."

Have a misfit as a main character 

Plot option No. 1: Do you just not fit in and coincidentally must also overcome some kind of hurdle — probably financial or social — to win the prize/girl/friends/whatever? Disney's got a story (or two dozen) for you. Whether it's the amateur inline skaters battling the professionals in "Brink!" or the outspoken, ribbon-dancing young girl who doesn't fit in at her new military school (or in her family) in "Cadet Kelly," standing out is "in" for DCOMS.

Related DCOMs: "Brink!"; "Johnny Tsunami"; "Johnny Kapahala: Back on Board"; "Genius"; "Alley Cats Strike"; the "High School Musical" movies; "Hounded"; "Cadet Kelly"; "Eddie's Million Dollar Cook-Off"; "Going to the Mat"; "Stuck in the Suburbs"; "Buffalo Dreams"; "Life is Ruff"; "Hatching Pete"; "Princess Protection Program"; "Lemonade Mouth"; "Starstruck"; "Geek Charming"; "Frenemies"; "Radio Rebel"; "Let it Shine"; "Bad Hair Day"; "Read It and Weep"; "Get A Clue"; and the "Camp Rock" movies.

Underdogs are top dogs

Overlapping with DCOM's affinity for misfits, the other go-to plot choice is a sports tale. Bonus points if the main character is not favored to win and must overcome adversity on the way to the finish line. Where else are you going to find a movie like "Motocrossed," about a girl who poses as her twin brother to win a race that her father wouldn't allow her to enter on her own?

Related DCOMs: "Miracle in Lane 2"; "Motocrossed"; "Double Teamed"; "Gotta Kick It Up!"; "Ready to Run"; "Right on Track"; "Full-Court Miracle"; "Go Figure"; "Jump In!" and "Cloud 9."

Believe in magic

The fantastical elements in DCOMs include everything from the ability to read dogs' minds ("You Lucky Dog") to the power to turn into a mermaid ("The Thirteenth Year") or leprechaun ("The Luck of the Irish"). It may actually be harder to find a storyline on the Disney Channel that doesn't have an otherworldly twist to it.

Related DCOMs: "You Lucky Dog"; "Can of Worms"; "The Thirteenth Year"; "Up, Up and Away"; "A Ring of Endless Light"; "The Poof Point"; "Stepsister from Planet Weird"; "The Other Me"; "The Ultimate Christmas Present"; "The Luck of the Irish"; "'Twas the Night"; "Pixel Perfect"; "Now You See It…"; "Twitches" and "Twitches Too"; "Minutemen"; "Avalon High"; "Zapped"; "How to Build A Better Boy"; the "Teen Beach" movies ;"Descendants"; "Wendy Wu: Homecoming Warrior" and "Invisible Sister." (There's also a subset of scary movies within this category, a genre that the kid-friendly Disney does surprisingly well: "Don't Look Under the Bed," all the "Halloweentown" movies, "Under Wraps," "The Scream Team," Mom's Got A Date with A Vampire" and "Girl vs. Monster" fit the bill.)

Family drama is always welcome

On a channel made for kids, it's implied that parents just don't understand, whether it's a computerized house who tries to act like the new mother of a family or Keaton's vehicle about inheriting a nephew after his father died.

Related DCOMs: "Northern Lights"; "Smart House"; "Horse Sense"; "The Color of Friendship"; "Rip Girls"; "Cow Belles"; "Phantom of the Megaplex"; "Quints"; "The Jennie Project"; "Jumping Ship"; "Tru Confessions"; "You Wish!"; "Tiger Cruise"; "Dadnapped"; and "Den Brother."

For every couple "Can of Worms" and "The Luck of Irish," make a "Color of Friendship"

The shining star in the DCOM lineup deftly touches on racial tensions in the 1970s as seen through the eyes of two teenage girls. "The Color of Friendship," the story of one black American and one white South African trying to live together in harmony, won an outstanding children's program Emmy in 2000.

Though DCOMs been on a bit of a popcorn-movie streak lately, they never used to shy away from emotionally difficult plot lines or true stories. "Miracle in Lane 2," based on the real tale of a disabled boy who learns to drive a soapbox, and "Going to the Mat," the fictional story of a blind wrestler, both garnered Directors Guild Awards for outstanding achievement in children's programs.

Related DCOMs: "The Color of Friendship"; "Miracle in Lane 2"; "Tru Confessions"; "Going to the Mat"; "Gotta Kick It Up!" and "Double Teamed."