Ephron isn’t the only one who’s hoping for a surge girlpower at the box office this summer. Hollywood traditionally counts on summer movies for the year’s biggest ticket sales, and kids’ movies are always a major part of the mix. (They’re the only moviegoers who demand to see their favorites five times.) This season has 17, from the magic-drenched “The Indian in the Cupboard” (opening July 14) to the battlefields of “Mighty Morphin Power Rangers” (June 30) and “Mortal Kombat” (Aug. 18). Merchandising tie-ins, by now a gigantic factor in movie profits, are piling up apace, with more than 1,000 products linked to the special-effects extravaganza “Casper” alone. But for the first time in memory, girls will be featured front and center in several of the summer’s most eagerly awaited movies, including the $50 million “Casper,” where Christina Ricci plays the young girl who befriends the friendly ghost, and Disney’s $55 million animated spectacular “Pocahontas.” A slightly older crowd – girls desperately seeking 13–will be giggling at “Clueless,” an affectionate take on Beverly Hills High and its bubbleheads. “As a producer and director, I’ve tried for years to get properties off the ground for girls, and I’ve been hitting a brick wall,” says Melanie Mayron, the actress and director of “The Baby-sitters Club,” based on the phenomenally popular series of books by Ann Martin. The brick wall is one of movie-dom’s most cherished truisms: both sexes go to boys’ movies, but boys don’t go to girls’ movies. Martin’s tens of millions of readers somehow didn’t strike anyone in Hollywood as a potential audience. Finally Lisa Henson, president of Columbia Pictures, said yes. “We haven’t neglected gifts here,” says Henson, who made “Little Women.” “Maybe it’s because I’m a woman.” (Gender loyalty wasn’t stretched too far: the film cost Columbia only a miserly $7 million.)

The producers believe all these girl movies will help one another at the box office. “We’re hoping ‘A Little Princess’ does really well,” says Marc Abraham, executive producer of “The Baby-sitters Club.’ . . . . Pocahontas’ is no question. That’s a neutron bomb.” And it’s been roaring toward us since February, when the video of “The Lion King” was released with a “Pocahontas” trailer attached to it. That became the biggest-selling video in history. Also since February, “Pocahontas” displays have been mounted at 20 malls across the country, with replicas of the sets and an interactive kiosk where visitors can “speak” in the voice of an animated character. The film and a stage show, together known as “The Pocahontas Summer Spectacular,” will open in six cities next month, following the premiere on June 10 in New York’s Central Park, where an anticipated 100,000 people will watch the film on four screens eight stories high.

But despite the juggernaut, most in the industry aren’t convinced “Pocahontas” will be as big a hit as the $312.8 million “Lion King.” . . . . Pocahontas’ doesn’t have the appeal of ‘Lion King’ because it’s historical," says an industry insider. “And because of the girl factor. Boys won’t want to go to a girl picture.” OK, OK, there’s a girl in it. Whether boys want to see her will be tested soon enough. But historical? A shapely Indian maiden leaping across mountaintops while her animal friends mug and sing? Kids, it’s make-believe. We promise.