What Makes Kids Intelligent?

Oct. 15, 2001 -- How can we make our children smarter?

A tough question, since some kids are book smart while others are street smart. Some build towering block skyscrapers while others paint word pictures in poetry and prose. Some win the school election while others know just what to say to make you feel better.

"Intelligence reflects the general ability to process information, which promotes learning, understanding, reasoning, [and] problem-solving," says Linda S. Gottfredson, PhD, a professor of education at the University of Delaware in Newark. "It affects many sorts of everyday behaviors."

As each child is unique, we'll focus on why children differ in intelligence, and on how to bring out their best.

Heredity or Environment?

Heredity accounts for more than 80% of the variation in adult intelligence, yet each successive generation appears smarter on IQ tests, highlighting the importance of environmental factors. Why the apparent contradiction?

"The hidden assumption in this paradox is that genes and environment are unrelated, which sounds ridiculous as soon as you say it," William T. Dickens, PhD, a senior fellow in economic studies at Brookings Institute in Washington, D.C., tells WebMD. "Genes get the credit for most of the work that the environment is doing."

Where intelligence is concerned, the rich get richer and the poor get poorer. Children born with higher intelligence do better in school, which enables them to get into enriched classes or go to college where they further their intelligence.

"If the environment affects IQ and the IQ affects environment, it's a virtuous or vicious cycle," Dickens says.

Over time, the effects of the environment on intelligence get weaker. For example, after a child enters a preschool enrichment program, IQ peaks within six to 12 months. When the child leaves that environment, IQ drifts downward.

"When you remove a kid from a good environment and put him back in a bad one, he'll do different things than he did before," Dickens says. "He may choose brighter friends or watch more educational TV shows. But there are fewer options than in the good environment, so, over time, there'll be a slow drag on his IQ."

Measuring Intelligence

How much stock should we put in those magical IQ numbers?

"I don't think there is much point in trying to assess children's intelligence unless they seem unusual -- not developing properly or precocious," Gottfredson says. "People tend to take individual test scores too seriously."

"A better indicator than IQ score is whether the child is curious, enjoys role playing and learning, and is happy," says Stephen J. Schoenthaler, PhD, a professor of nutrition and behavior at California State University in Long Beach.

But Dickens contends that the one thing that best predicts how well 14-year-olds will do as adults, in terms of economic and social outcome, is their IQ score.