Several years ago, my then-fourth-grade son came home with an assignment. "I'm supposed to write a CD manufacturer to protest the way its unnecessary packaging is hurting the environment," he said. "Why would a company increase its costs by paying for packaging that's truly unnecessary?," I asked. "Maybe the packaging makes CDs harder to shoplift, or easier to see on display racks. Did your teacher tell you to research this first, or ask for the company's side of the story?" "No," he said, with a surprised look. "I'm just supposed to tell it to stop."

These days, facts frequently take a back seat in the environmental education our children receive at school. Too often, environmental instruction seems to aim -- not at a disinterested search for the truth -- but at convincing children that "the planet" is in imminent danger, and they must save it.

Now parents who want a more balanced perspective have a valuable new resource: "Facts Not Fear: A Parent's Guide to Teaching Children about the Environment," by Michael Sanera and Jane Shaw. In preparing their book, Sanera and Shaw reviewed hundreds of children's environmental books, and found that most present only one side of an issue, or select worst-case scenarios. By contrast, "Facts Not Fear" reviews the evidence on issues from global warming to species extinction, and demonstrates that many supposed "crises" are greatly exaggerated, or have little basis in fact.

Why are children's books so biased? Sanera and Shaw say most share two emotionally powerful ideas, which lead them to treat environmental education as a morality play, not a scientific inquiry. The first idea is that "nature is good and people are bad" -- ditto for consumption, business and technology. The second is that only government can devise effective solutions to the environmental problems we face.

Contrary to what children's textbooks say, the best way to ensure a healthy environment is to foster a dynamic free market economy. Wasteful and inefficient use of resources is the No. 1 cause of pollution. A vibrant economy -- especially one that has moved from the industrial to the information stage -- tends to use resources ever more efficiently, and to ensure a rapid turnover of older, less efficient equipment. (In the 1960's, for example, it took 164 pounds of steel to produce 1,000 soft drink cans; in 1990, 35 pounds of aluminum did the job.) Only a prosperous society has both the will and means to make environmental protection a top priority.

Government clearly has a role to play in protecting the environment -- air pollution is a case in point. But overregulation saps the economic dynamism vital to technological progress, and can actually be counter-productive.

The Endangered Species Act is a case in point. By giving the government power over land where certain species are found, it lowers the land's value, and so gives owners an incentive to make their property unattractive to the very species the law seeks to protect.

If our children are to meet their environmental challenges, they must move beyond thinking in terms of good guys -- Greenpeace and people who "care about trees" -- and "bad guys" -- General Motors and people who eat at McDonald's. Young people don't need a morality play, but a thorough grounding in science and economics -- and the ability to weigh costs and benefits, which is central to wise policy-making.

-- Katherine Kersten is chairman of Center of the American Experiment in Minneapolis and a commentator for National Public Radio's "All Things Considered."