The "High School Musical" film franchise just hit its big 20th anniversary ... and we’re celebrating with a Guess Who gallery!

Fair warning -- this one’s gonna be tough. These pics span years ... and they're all grown up now, so ... Good luck, Wildcats!

If you’re still craving more HSM, then get ya head in the game and test your Wildcats knowledge with a little word search!

Honestly, it’s one massive throwback -- and we’ve also pulled together all the most iconic scenes to celebrate the franchise that launched Zac Efron, Vanessa Hudgens, and a whole generation of Disney stars.

Troy and Gabriella, 4ever. 🏀🎤