JUST SAY ...

For Justin, a history teacher and the father of two teenagers, the moment of drug anxiety came when his children were in elementary school. They had just been to a DARE drug education class and informed him "that it's a totally bad thing to take drugs," he said.

Though he approved of the overall message, their zeal put him in a fix. Justin, 50, who declined to use his last name, smokes marijuana two or three times a week. What could he tell his children without appearing to condone drug use? "I said, 'But not all drugs are bad, are they?' "

As anyone who came of age around the smell of marijuana knows, drug use was supposed to follow a passing narrative arc: You had your youthful experimentation, you learned your lesson, you grew up and out of it. But for many, like Justin, things have not worked out that way. Years after the battles about drugs with their parents, they are facing another generational hurdle - how to reconcile their marijuana use with the demands of raising their children.

In many cases, they are moderate users who manage careers, families and social lives while sneaking an occasional joint. Most say they smoke for the same reasons they always did: to relax, listen to music or socialize. After two or more decades, they see little harm.

"We never study those people," said Dr. Roger Roffman, a professor of social work at the University of Washington, where he has studied marijuana use since 1983. He likened this group to the majority of drinkers, who do not progress to alcoholism.

Though statistics involving drug use are notoriously slippery, as many as 1 in 10 American parents of children younger than 18 - about 6 million people - said they had smoked mari-juana in the preceding 12 months, according to a poll conducted last year by RoperASW. The poll, sponsored by the Partnership for a Drug-Free America, included interviews with 1,219 parents.

Because the topic involves both illegal mari-juana smoking and children, most people interviewed for this article were highly circumspect, often unwilling to use even their first names.

With decidedly mixed feelings, many are now repeating the ruses of their adolescence, sneaking out on ledges as they did years ago, wondering what they'll say if they get caught.

One man said he stuck to the tried and true, hiding his weed in the same Rolling Stones album cover he used as a teen. He figures his children are no more likely to stumble across it there than his parents were.

Parents, of course, have many secrets from their children, including their finances and the details of their sex lives.

But marijuana use comes with a unique set of conflicted feelings. For many, it still resonates as a triumphal rite of passage and stirs reminders of their own parents' cluelessness.

Joseph A. Califano, president of the National Center on Addiction and Substance Abuse at Columbia University, criticized what he sees as a generation refusing to grow up and take responsibility, inflicting its habits on its children.

"There's a big disconnect in values today," Califano said. "Parents of the '70s by and large think marijuana is less dangerous than (do) teenagers of the 2000s. Parents of the '70s have mostly grown out of it, while kids see what happens to potheads in their classes."

In the short term, marijuana can impair memory and judgment, research has shown; the smoke is also carcinogenic.

Califano advised that parents be honest about their past use.

The problem for those parents is a sticky one. From their own experiences, many do not consider the occasional joint a great hazard. But they fear their children smoking too often or too early in the hothouse years, when every whim tends to be taken to excess. While they draw a line between moderate use and problem use, they cannot assume their children will do so.

Even moderate drug use can put parents in an awkward position with their children, inverting the family roles. "I have to stand up straight and not be goofy," said a New Jersey man named Frank, 50, who has two daughters, 21 and 16. "They say, "Dad, what's up? You're acting stupid.' It's very similar to when I was busted by my parents."

Drug counselors warn that parental use, even in secret, can influence the behavior of children. In a 1999 survey of nearly 600 teenagers in drug treatment, one in five said they had used drugs with a parent.

As the first wave of the counterculture ages, some members are facing the next challenge: hiding their marijuana use from their grandchildren. Nearly 100,000 Americans over 60 smoke marijuana occasionally, according to the 2000 National Household Survey on Drug Abuse, a government study based on interviews with 71,764 people.

One suburban publishing professional with adolescent grandchildren said that in his 60s, he found marijuana a particularly gentle pleasure. But when his grandchildren visit, he goes into deep cover. "I've even taken to rolling cigarettes in front of them, just in case they find a roach."