Two years after a national report launched a full-scale revolution in American classrooms, one sticky problem has stubbornly resisted the tide of education reform: high school dropouts.

The figures themselves are staggering -- a quarter of American students leave school and never return. In some big cities, the dropout rate is nearly twice that. They are the products of poverty, but also the children of affluence.

"Dropout," Capital Cities' ambitious effort to examine this complex problem, consciously avoids the TV documentary's usual pitfall. The problem is not clear-cut; the answers are not easily summed up and canned in 60 minutes, minus commercials. It takes a look at four places, including Washington, where dropout prevention programs have made a dent in what it rightly calls "the hemorrhage in our schools."

"Dropout," which airs at 9 tonight on Channel 5, succeeds despite the monotone narration from former head "sweathog" Gabe Kaplan ("Welcome Back Kotter"), who starts out warning viewers, "This report does not attempt to deal with any long-term solutions."

The real stars of this show are the dropouts themselves. There's Eldrea, the lanky high-school drug dealer who casually recalls shooting a customer during a parking lot chase. And there's Billy, a Knoxville teen-ager who says candidly to the camera: "My parents thought I was smoking pot -- they didn't know I was eating acid."

Their words are stirring, constantly reminding viewers that the dropout problem is the product of a cross-cutting set of seemingly intractable social crises -- drug abuse, alcoholism, violent homes and teen-age pregnancy.

The teachers and counselors who have run successful dropout centers have succeeded precisely because they acknowledge the enormous problems that lead teen-agers to quit school.

For example, the woman running the Knoxville center concedes that as long as there are high schools in America, there will be drugs and kids using drugs.

The center also offers classes on parenting for young mothers, and Rule High School in Knoxville has set up a program that allows teen-aged mothers to bring their infants to school with them, as an alternative to dropping out.

Eldrea and Billy and the other teen-agers profiled all succeeded after failure, and if anything this show offers an overly optimistic look at the problem. If only similar dropout prevention programs were set up everywhere, Kaplan says, the dropout problem could be conquered. He neglects to add that all it would take would be about a billion dollars, at a time when the federal government is cutting funds and scaling back programs.

One of the more unusual dropout centers examined is Atlanta's "School of Last Resort," run on the top floor of Rich's department store, which is part of the Bloomingdale chain. The students attend Rich's academy in the morning, before the store's opening hours, to hear lectures from Rich's managers and other local merchants. That segment provides a rare display of the business world committing resources and time to a pressing social problem.

Coming as Congress is debating budget cuts and priorities, "Dropout" is certainly a timely contribution to the ongoing national debate.