Leah Benz, 12, left, and Rachel Benz, 9, rehearse their parts in the Theatre By The Sea production of George M! to be performed in a preview showing tonight.

The Providence Journal / Kris Craig

SOUTH KINGSTOWN — Starting tonight, 9-year-old Rachel Benz and her sister Leah, 12, can misbehave and be applauded.

The Narragansett girls auditioned for — and won — parts in Theatre By The Sea’s production of George M! But being naughty is only part of what the sisters will be doing in this musical biography of Providence-born showman George M. Cohan, which opens for previews tonight at the Matunuck theater.

They’ll also be wearing beautiful costumes, playing street urchins, and singing a duet. They’ll report to the theater Tuesdays through Sundays to dance, wear makeup, and see their names listed in the playbill.

“I would actually dream about being in a show here,” Leah says, recalling how she felt after seeing her first play at the summer theater, a 2001 production of The King and I.

“We feel so professional,” cuts in Rachel.

“We’d rather be here than sitting on the couch watching TV,” big sister says at the theater’s Wakefield rehearsal hall.

Little sister nods, eyes flashing a you’re-so-right-look.

WHILE SCHOOL is still in session at the Narragansett Elementary and the Pier Middle schools, where they are finishing fourth grade and sixth grade, the girls and their parents are finding a way to do it all.

“Our school work is very important to us,” said Leah. “We’re working really hard to keep up. We bring our homework and do it here. There’s a lot of downtime.”

No, there aren’t any field trips being missed. No, they don’t have summer jobs yet to cause a conflict. Sure, they know they could get tired at the end of the day.

“It’s bad and good,” says Rachel of the sacrifices being made.

“But it’s a thrill to be onstage,” adds Leah. “I thought about this for a long time before I decided we have nothing to lose.”

THEY’VE BOTH been onstage before, happily involved in productions of the Fantasy Works Youth Theater, spending a good part of summer days with “other kids who have the same passion for singing and dancing that we do,” said Leah, who also appeared in a school production of Guys and Dolls Jr. last fall.

They’ve performed in Annie, The Music Man and Aladdin, never bothered that the beach is just a few blocks away from the stage where they rehearse on hot summer days.

“It’s amazing how it all comes together,” said Rachel maturely.

Their Theatre By The Sea parts, Rachel says, are roles as “first little girl and second little girl,” but they face the audience numerous times.

“We get to talk back to people,” Rachel said.

Do they do that offstage?

“NO!” they both responded.

DIRECTOR AIMEE TURNER said the girls stood out at auditions with about 40 other children.

“They are just as smart as can be,” said Turner, “and they come in smiling, which is always a good sign.”

Turner, who has two children of her own, said the biggest challenge in weaving children into this theatrical production is that “school’s not out. But their family and the school have been so supportive.”

It’s a big commitment, she said, for the girls and their family.

The girls will be missing their own dance recital, and several family functions, said their mother, Jamie.

“Rachel’s 10th birthday is June 25. She’ll be doing a show,” she said. “They have to make sacrifices to do it. They’ll either love it or hate it, and then we’ll know. It’s a good experience.”

THEATRE BY THE SEA is where Jamie Benz attended the theater as a youngster, and where her husband played in the orchestra for three summers. The couple expect to see their daughters perform at least a half-dozen times, she said, and family members, friends, teachers and schoolmates will be there often, too.

“We are so grateful for our dad’s help,” Leah said. Dad is Fritz Benz, band director at North Smithfield High School, and he has offered his girls his musical expertise.

“We owe it all to our mom,” said Rachel. “She’s the one who told us about [the auditions].” And, she says, mom is doing a lot of driving to rehearsals and to the theater, despite her job as a Coventry High School Spanish teacher. During her time off, Rachel knows her mom would “rather be at the beach.”

The girls’ music teacher, Maria Day Hyde of North Kingstown, has helped them with this music they have never heard before. It’s not like it’s the score from Wicked, which they know by heart. The early-20th-century music of George M. Cohan is something different altogether.

Other Rhode Islanders appearing in the cast are Jonathan Cooper of East Greenwich, Kimberly Kalunian of Warwick, Kevin P. Martin of Cumberland and Sarah Pothier of Rumford.

The girls said they’re interested in exploring the difference in putting on a weekend show, as they do in Fantasy Works, and being part of a Tuesday-through-Sunday schedule, two shows on Thursdays and Saturdays.

Said Leah: “We want to show everyone that we can handle it.”

George M! will be presented tonight through July 12, with preview performances tonight and tomorrow, and opening night slated for Friday. Performances are Tuesday, Wednesday, Thursday and Friday evenings at 8, Thursdays at 2, Saturdays at 4:30 and 8:30 p.m. and Sundays at 5, with special performance times on Sunday, June 22, at 3 and 8 p.m. and a special Wednesday matinee on July 9 at 2 p.m.

Tickets start at $35. $15 student rush tickets will be available on a limited basis one hour before curtain on the day of the performance with a student ID. To reach the box office, call (401) 782-8587. Tickets may be ordered online at www.theatrebythesea.com.

afleming@projo.com