Newsround managed to stop High School Musical star Olesya Rulin - who plays Kelsi Nielsen - from singing and dancing for five minutes to have a quick chat.
So what does she have to say about Kelsie's dress sense, hanging out with Ashley Tisdale, and High School Musical 4?
You've been in all three high school musicals so far. Which one did you enjoy being in the most?
In the first one you're getting your bearings and figuring out how things work. We've had the same crew for three-and-a-half years, so it became a really tight family. By the end of the third one it was like a summer camp. So probably the third one was my favourite.
How like your character are you?
We both wear glasses! And I wear a lot of caps and fedoras. I was a bit shy in high school, but not as shy as Kelsie.
Your character is what we call a bit frumpy. What's that like to play?
It does make it harder. I think I have some fashion sense, so it was difficult. Some of the other actors were wearing cute pink outfits, and I was in jumpers! But in the third movie she grows a lot style-wise. I enjoyed that she had grown and become really confident.
Do you write music yourself in real life?
I'm not musically inclined. It blows my mind that people can write music. I don't have that talent, I look up to the people that do.
What's your fave song so far?
I really like Humuhumunukunukuapua'a from the second film and Scream from High School Musical 3.
And how about your fave dance routine?
I loved learning the waltz for the third movie. It was cool to have classical dancing at a high school prom.
High School Musical is huge here in the UK. Have you been to the UK, and what do you think of British fans?
I've been to the UK a lot, like five times. I love it! The British fans are awesome.
We were there for the HSM2 premiere and had a great signing session in a big store in London. I love British musicals too.
I saw Billy Elliott in London and cried so much that the lady next to me thought something was wrong. It's in America now too, but it's not the same in New York.
And what about other countries in the world - where has HSM taken you?
More states than I can name in America. I just went to China for High School Musical which was really fun, and I've been to Canada and Europe too.
After being in all three you must be pretty famous. Do you get recognised, and what's that like?
It's sort of bizarre, but it's nice to be recognised. I don't get recognised too much because Kelsie wears a hat and glasses and I normally just wear sunglasses.
I can be hanging out with Ashley and everyone comes up to her but they don't realise I'm there next to her.
We often see people dressed as characters from the films. Have your spotted anyone dressed as Kelsie?
It's really cute when we go to premieres. I see lots of little girls in hats and glasses like Kelsie. It's crazy and surreal and really flattering.
Are you friends with anyone from the films?
We spent three-and-a-half years working together and are like a family. We're always having barbecues and parties and everyone chats to each other all the time. I hang out with Ashley tons. We hang out and watch movies together.
What tips would you give to kids wanting to get into acting and dancing?
It's okay to have a bad audition. People want perfection so much and it can be really stressful. If it goes badly then go home, take a deep breath and try not to worry too much. Try not to make the same mistakes the next time.
Apparently there is a script for High School Musical 4? Do you have a role in that too?
Kelsie has graduated, she's gone from high school - she's in Juilliard already.