THERE'S GOOD NEWS on the handbasket front. We may not be going to hell in one after all, at least not right away.

The latest reprieve: Teenage birthrates plunged 21 percent from 1991 to 1996, and tentative data since suggest the decline is continuing.There are few less welcome messengers than one bringing good news to a polity that loves to think, as ours seems to, that things are looking bad rather than up. Still, and sorry if this is disillusioning, there's no getting around the fact that many key social billboards are cheery.

The economy grows steadily and so far without exciting the inflation that would turn on it. What's more, the expansion isn't being bought, as was the more-bubble-than-boom growth of the '80s, by overboard deficit spending and real estate fiddles.

Crime is down significantly, though you'd never know it from our gangbuster politicians. Serious crime fell 3 percent in 1996, the fifth decline in a row. Murder was at the lowest level since 1969. Juvenile crime, too, plunged 9.2 percent that year, its second sharp decline. The biggest roll-off is in violent juvenile crime. Interim numbers suggest those drifts also are continuing.

Even divorce is slipping. The rate peaked at 5.3 per 1,000 of us in 1981. At mid-'97, it was running at 4.3.

The lowering teen pregnancy rate has cranked our culture warriors, with the abstinence and the contraceptive crowds equally claiming credit.

Credit both but contraception the more. The lowest teen pregnancy rates, under 30 per 1,000 of population, are in the politically liberal or moderate states - New England, Wisconsin, Minnesota, Hawaii - that typically aren't condom-shy. The highest, over 50 per 1,000, are in the abstinence belt - much of the old South, plus Oklahoma and a few others. Europe, with teens as sexually active as ours but open about birth control, has far fewer teen pregnancies.

Two other factors count. Teen childbearing marches in near lockstep with the economy, and the boom is giving poor girls enough hope for the future that delaying pregnancy makes sense. And fear of AIDS is overriding macho disdain for condoms, especially among black teens, where the pregnancy decline is by far the largest.

But we're piling up future woes by imprisoning far too many for far too long for nonviolent offenses; many will come out mean. Though we're educating record numbers of our kids well enough, we are failing others badly. The strong but still tenuous African-American movement into the middle class in recent years is threatened by affirmative action rollbacks.

We indulge a degree and a depth of poverty no other developed nation allows. A rising economy just swamps the moored boats. The rich-poor gap is widening, and an appalling 20 percent of our kids are growing up in poverty, a huge long-term liability.

Even so, the still-better news in the good news is the heartening evidence that when we work at social problems steadily and sensibly, we really can make a sounder national life for ourselves. Can you stand the optimism?