WITH AN EYE ON . . . : The future career of Sarah Polley depends on one audition--<i> seriously</i>

Sarah Polley, who plays Sara Stanley on the Disney series “Avonlea,” is not the sort of actress who counts the number of lines she has in each script.

In fact, throughout the five seasons of the show based on Lucy Maud Montgomery’s children stories, Polley has asked to be in fewer and fewer shows. Next season, at her request, she’ll only be in one episode of “Avonlea.”

Asking for less time may sound odd for a 15-year-old performer whose role was the initial focus of the show, but Polley is determined. “I want to be a writer and a political activist,” she says from her home in Toronto.

In fact, her acting career now hinges on a feature-film role she’s up for. If she gets the part, which would take her to Los Angeles, she says she’ll continue acting; if not, she says she’ll focus on her education.

“It’s a pretty serious time for me,” she says. “The film is actually something I really want to do. Basically, it (my career) depends on if I get that part.”

Her career began when she was 4 in the feature “One Magic Christmas,” followed by “The Big Town” and “Pretty Kill.” She starred in the Canadian series “Ramona,” which is available on video.

“It boggles my mind how together she is,” says “Avonlea” producer Kevin Sullivan. “She wants to go to Oxford, where her father went, and she’s determined to do it. She’s worked long and hard at acting. She’s seen what it has done to fellow actors.

“She grew up in an acting environment and spent a year on a huge production, ‘The Adventures of Baron Munchausen.’ ”

Polley turned 9 during the 1988 filming of the troubled, big-budget Terry Gilliam film, which was shot in Italy and Spain. It starred Gilliam’s “Monty Python” pal Eric Idle, as well as Oliver Reed, John Neville, Uma Thurman and Robin Williams.

When casting his Disney film “Lantern Hill,” Sullivan says, “she was the only actress I knew of anywhere in the world who had the technical skill behind her and had the wide range of emotion.”

He found the Canadian actress’ ability to do accents right on target. Says Sullivan: “She used a Cockney accent for ‘Lantern Hill’ and has also used an English accent.”

Critics have also praised Polley. In her “Munchausen” review, The Times’ Sheila Benson says Polley “seems to have been blessed oblivious to any child-acting cliches.” In Lynne Heffley’s review of “Avonlea” in The Times, she calls the actress “one of the most beguiling child actors around.”

Sullivan says that the transition from child actor to ingenue is a difficult one, but he thinks that if she chooses an acting career, Polley has the ability “to become a (Meryl) Streep, a star performer. Her skills are much more sophisticated than other professionals.”

Next week’s “Avonlea”--which has evolved into an ensemble hourlong show--will focus on Polley’s Sara Stanley’s first kiss.

Polley has only one other acting job lined up. She’ll play the lead in “Alice Through the Looking Glass” at the Stratford Shakespearean Festival in Ontario, Canada. “It’s something I’m interested in doing,” she says.

Since Polley knows what else she wants to do, the time away from acting isn’t daunting. “I’ve been working since I was four and this is the first big open space I’ve left for myself. I’ve always had two jobs lined up. Now I’ve set my sights on an alternative future.”

“Avonlea” airs Mondays at 8 p.m. and repeats the following Sunday at 6 p.m. on the Disney Channel.