Are teenagers basically nuts? Michael J. Bradley thinks so. An educational psychologist and therapist, Bradley's the author of "Yes, Your Teen is Crazy! Loving Your Kid Without Losing Your Mind" (2003, Harbor Press, $14.95). Bradley has also authored "Yes, Your Parents Are Crazy! A Teen Survival Handbook," so one wonders if he thinks everyone's nuts to begin with.

But seriously, Bradley points out that while 95 percent of the brain develops in early childhood, the most advanced parts aren't "complete" until late adolescence. In other words, teens aren't playing with a full deck, the result being that they sometimes appear unstable, irrational, impulsive and downright stupid — in a word, nuts. Compounding the problem for today's teens is the fact that popular culture encourages wrong values and wrong thinking as well as downright stupid behavior. So teens have always been crazy, but of late it's become especially difficult for them to project even a semblance of sanity.

Bradley's thesis is interesting (if not original), and he manages to give reasonably practical advice (although I take issue with some of it) within what is, overall, an entertaining read. But the exceptions disprove Bradley's rule. Let's face it, a significant number of teenagers don't act like they've got loose screws rattling around inside their craniums.

My favorite cousin's two children, for example, are in their teens, and neither of them has ever done anything outrageously irrational. They're respectful, well-mannered, responsible young people who are a pleasure to be around. Assuming my cousin is telling the truth, they've never even been especially moody, and no, neither child has been lobotomized. She also claims that her kids' friends seem to be rational and responsible as well. This is not some Stepford Teen phenomenon in suburban Atlanta, because my cousin's testimony is consistent with firsthand reports from many parents around the United States. Indeed, some teens act deranged regularly, but so do some adults, and the proportions may be approximately equal.

The historical evidence mitigates Bradley's thesis as well. Writing in the mid-1800s, Alexis de Tocqueville ("Democracy in America") described the American teen as responsible, hard-working and community-minded. About the worst descriptor any contemporaneous critic attached to the pre-modern teenager was "mischievous," the archetype of which was Mark Twain's Tom Sawyer, and mischievous seems to have been the norm until the 1960s.

If hormones and immature brains are the problem, then the only conclusion to draw is that these physiological variables are the result of some aspect of modernity — fluoride in the water, perhaps? My opinion of Bradley's hypothesis is: interesting but no cigar, which is not to say it isn't recommendable to parents whose kids fit the profile, because it is. But Bradley sells books to those parents precisely because he enables their denial. By advancing a thesis that is shaky at best, he absolves them of responsibility for the fact that their children exhibit toddler behaviors — tantrums, defiance, self-centeredness — well into their teenage years (and beyond?). The mere fact that perpetual toddlerhood disorder does not afflict most teens says that parents are primarily responsible, either way.

Some parents expect responsible behavior; others say they expect it but then turn around and enable irresponsible behavior. Some parents teach and expect good manners; others would like to believe they fall in that category, but they don't. Some parents glorify materialism; others do not. Some parents give in to tantrums; others do not. Some parents promote high self-esteem; others promote humility and modesty. Some parents allow their children to become absorbed in pop culture through electronic media; others do not. Some parents cater to their children at mealtimes; while others expect their children to eat what they are served. From early on, some parents have their children doing household chores; others put their kids on never-ending entitlement-and-enabling programs. I'll stop there. I'm sure you get my point, whether you're comfortable with it or not.

Parenting does not make the child, but it's a huge influence on the making of the child. Therefore, huge differences in parenting are going to result in huge differences in child behavior. That's the way it's always been, and that's the way it's always gonna be.

Family psychologist John Rosemond answers parents' questions at www.rosemond.com.