Why do Singaporeans love musicals? Dream Academy founder Selena Tan jokes: "Because we are Sing-a-pore, mah."

Music and comedy form the backbone of her for-profit production company, known for the Dim Sum Dollies revues and Broadway Beng shows.

Tan's latest musical also marries melodies and mirth. Detention Katong, opening on Friday next week at the Esplanade Theatre, is a coming-of-age tale about a good schoolgirl (Valerie Choo) gone bad. Female stars Inch Chua and Munah Bagharib play her schoolmates.

Their teachers are played by an all-star cast: Suhaimi Yusof, Neo Swee Lin, Darius Tan and Sebastian Tan.

Why focus on schoolgirl stories? "I couldn't get more boys to sing," says Selena Tan, who wrote the book and lyrics.

Also, she was reminded when her niece began attending secondary school that power dynamics among students are different in an all-girls school, an all-boys school and a co-ed school. "Boys will beat one another up. With girls, there's a lot of psychological warfare going on."

The 46-year-old should know. She attended the all-girls St Theresa's Convent school as well as the co-ed Fairfield Methodist Secondary School.

Every cast member has school stories to share in rehearsals. Chua, 28, speaks of the time her hair was accidentally cropped too close, leading to a fashion crisis. Suhaimi, 47, recalls a teacher whose best friends were her stuffed toys and another who tried in vain to get his class interested in current affairs.

Tan says: "School is part of your life that's just stamped in. You never lose it."

The Detention Katong soundtrack is written by an eclectic bunch of composers, including Tan's brother Roy (of the band Leos And Virgos), theatrical music mistress Elaine Chan, Benjamin Kheng of The Sam Willows, Dave Tan of Electrico and singer-songwriter Sarah Cheng-De Winne.

Selena Tan brings big guns to bear in her musicals for several reasons. First, soundtrack sales can help recoup the $1.6-million production cost. Second, she has never forgotten the time in Australia where a stand-up comic made a joke about her being from Singapore.

"He said, 'So, you sing-a-poor?' I was like, 'No! We sing good!'"