So, you know how we all grew up watching High School Musical, right? I mean, who didn't have a secret crush on Troy Bolton or wish they could sing like Gabriella Montez? But have you ever stopped to think, "Hey, how old were these actors when they were actually in high school?" Let's dive in, shall we?

Zac Efron - Troy Bolton

Now, Zac was born in October 1987, which makes him a Libra, in case you're into that astrology stuff. When he was cast as Troy, he was 16, but he looked a bit younger, didn't he? I mean, who could resist those baby blues?

Interestingly, when the first movie came out in 2006, Zac was 18. Can you believe it? He was already a senior in high school, or at least, his character was. I guess that's showbiz for you - looking younger than you are!

Must Read

Vanessa Hudgens - Gabriella Montez

Now, let's talk about our girl Vanessa. She was born in December 1988, making her a Sagittarius. When she stepped into Gabriella's shoes, she was 17. Just a year older than Zac, but they pulled off that whole "new in town" thing perfectly, didn't they?

Fun fact: Vanessa was actually a senior in high school when the first movie was released. I know, right? It's like they were both living the high school dream, even if it was on screen!

Ashley Tisdale - Sharpay Evans

Now, Ashley was born in July 1985, making her a Cancer. When she first graced our screens as the fabulous Sharpay, she was 20. Yes, you read that right. She was playing a high school student when she was already in her twenties!

Haarlak De Musical CastHaarlak De Musical Cast

But hey, who cares? She totally nailed the role, and we all loved her for it. Plus, she was the perfect mean girl, don't you think?

Lucas Grabeel - Ryan Evans

And last but not least, we have Lucas. Born in November 1984, he's a Scorpio. When he was cast as Sharpay's twin brother, Ryan, he was 21. Yes, you heard it here first - he was the oldest of the main cast!

But seriously, who would've guessed? He pulled off the high school look like a pro, didn't he?

So there you have it, folks. The ages of our favorite High School Musical stars when they were actually in high school. It's crazy to think they were all older than their characters, but hey, that's showbiz for you. It's all about looking the part, right?