BOSTON — YOUNG people - and many adults, for that matter - are snubbing newspapers. In an effort to cultivate new consumers, many papers in the United States are developing special sections or pages for young readers.For a long time, editors assumed that once students went away to college they would start reading the paper or once they got out of college they would start picking it up, says Bruce Raben, an editor with the Fort Worth (Texas) Star-Telegram. "Well, they weren't," he says. In 1990, 53 percent of 18-to-24-year-olds read a newspaper every day - compared with 73 percent in 1970, according to the Newspaper Advertising Bureau. "We decided to go back to basics and try to get 'em in the habit of reading at a very young age," Mr. Raben says. In September 1989, the Star-Telegram launched "Class Acts," a colorful weekly section aimed at seven-to-14-year-olds. The tabloid pull-out includes serious articles on drugs and homelessness as well as fashion and entertainment features. A Fort Worth 14-year-old provides cartoons, and about 40 percent of each edition is written by young contributors. "Class Acts" has quickly generated a loyal following. Contests and promotions in the section are getting remarkable results. A phone contest last year brought in 246,000 calls in 23 days. Past attempts at providing just-for-kids sections in newspapers have been sparse - and most target young children rather than teens. "The Mini Page," an insert aimed at preteens, has been syndicated by Universal Press Syndicate for more than 20 years. But as declining revenues have forced newspapers to cut back, many have dropped such features. "When papers started to figure out ways to save money, 'The Mini Page' was always the first thing that went. It was a drain; it cost you money, took up space, and there was no potential for revenue," Raben says. Last year, "Class Acts" produced a profit for the Star-Telegram. The New York Times's syndication service recently started offering it to subscribers. Along with the trailblazing Star-Telegram, other newspapers are reaching out to the largely untapped youth market. For example: * The Syracuse (N. Y.) Herald-Journal publishes a weekly section called "hj." The 12-page pull-out focuses on high-schoolers and tackles such serious issues as dropouts, racism, teenage crime, and homosexuality as "The Big Story" in each issue. The Herald-Journal - which began publishing "hj" weekly in April 1990 - employs one student correspondent from each high school in the area. "A lot of the items they write have ended up on Page 1 [of the regular edition]," says Grant Podelco, the Herald-Journal editor who oversees "hj. 'hj' was sort of the showcase for a while, but we've slowly incorporated our coverage of teenagers into the rest of the newspaper as well," Mr. Podelco says. * The Washington Post recently created a weekly page labeled, "Under 21: Fresh News and Your Views." * The Chicago Tribune now includes a daily "Young Readers' Guide" alongside its regular index. In January, the Tribune plans to launch a weekly section for "tweens kids age 10 to 13. "Up until age 12 and 13 is about the last time you can get boys and girls reading the same section," says John Lux, associate features editor. "There's still that interest in animals and the same kind of rock-and-roll stars. After that, the kids tend to branch off, and we hope then to hook them in our regular paper." As of yet, there is no definitive evidence that these tactics are increasing newspaper readership, says Gwen Kirk of the American Newspaper Publishers Association. But research is under way. "As this trend develops, we'll find out if this is reaching the youth, developing reading skills, and increasing readership," he says.