* Nonfiction. By Richard E. Nisbett. Norton, $26.95. Grade:B+

Book in a nutshell: Nisbett, a professor at the University of Michigan, aims to overthrow the idea that our intelligence is fixed at birth. This is the "hereditarian view . . . (that) you are only going to be as smart as your genes allow," he writes. Instead, he argues that our cultures, schools, and socio-economic status all have a far greater impact on our IQ than our genes.

Nisbett considers improvements in intelligence (the "ability to solve problems and to reason") over the past 60 to 100 years, noting that not only have our schools improved, but that children are spending more time in them (from seven years a century ago to 14 now). He then looks at the different cultures (notably East Asians and Jews) whose children typically out-perform Western kids in grades, IQ, and standardized test scores. At early ages, most kids from all cultures in similar environments tend to perform roughly the same. But by high school and college, Jews and Asian-Americans surge ahead, indicating that environment, not genetics, is what makes certain kids smarter than others.

So race does matter - but not in the way we have assumed. Jews and Asian-Americans are likely more intelligent because their cultures have emphasized and valued learning for centuries, if not millennia.

Thus, the case for improving schools and reorienting our culture toward the value of education becomes a more urgent proposition. We can make ourselves smarter, and Nisbett offers a quick-start guide in the final chapter ("Raising Your Child's Intelligence . . . and Your Own") to get us going.

Best tidbit: American IQ scores have improved approximately 30 points on average over the past century. This is not a genetic change but the result of dramatic improvements in education.

Pros: This is impressively accessible and engaging for a book written by an academic.

Cons: Academic jargon still creeps in: a glossary of unfamiliar terms would have helped.

Final word: It appears that we can no longer blame our parents for our lack of brains, but if our culture doesn't start to emphasize learning, now our kids can blame us.