But there's another device in your home that can help develop language and visual skills. It's called _ hold on to your remotes _ the television set.

Instead of being simply society's whipping boy and the root of all cultural evil, the so-called "idiot box" might actually boost test scores, especially in disadvantaged homes, a recently published study out of the University of Chicago says.

Even as it baby-sits electronically, the TV can be teaching both modes of learning and facts, other studies suggest, and keeping those who watch it from engaging in more destructive behaviors.

That's the good news about the boob tube. There's certainly bad, including the warning that "there's no two-dimensional screen that can equal a three-dimensional caregiver," says Dr. Donald Shifrin, the American Academy of Pediatrics spokesman on the impact of media on children. Then there's the study showing kids who watch more TV do less reading.

But we'll get to the numerous caveats _ especially the one about "Desperate Housewives" being less helpful than "Sesame Street" _ later.

For now, let's deal with what many may find surprising.

The prevailing, almost unquestioning cultural bias against TV, especially among the upper-middle class, is nailed by the humor blog Stuff White People Like, which puts "Not having a TV" at No. 28 on the list.

"The number one reason why white people like not having a TV is so that they can tell you that they don't have a TV," the authors write. But there is an academic consensus, if not a popular-culture one, that TV may actually be useful as more than just a means for frazzled parents to buy a few moments of uninterrupted time or wind down mindlessly at day's end.

"I used to laugh and say, 'I did 25 years of research on children in television, and I can summarize it in one sentence: It's the content that matters,'" says Aletha Huston, a professor of child development at the University of Texas.

"If used correctly, television can be a wonderful medium for kids. It can be a way of exposing them to the world. It can be a resource for kids to get to places and times they wouldn't get to," says Huston.

Yet, "it is a message that doesn't get out there somehow," she says, citing the surprisingly intense interest when "we published a study a few years ago showing the positive effects of 'Sesame Street' on early schoolkids' performance."

The Chicago study came out of the Graduate School of Business, where young economists have been looking at media and its effects. Although based on an old data set, it offers new confirmation of the evolving views of television.

Standardized testing of almost 350,000 6th, 9th and 12th-grade students showed that the students who had more exposure to television in early childhood did slightly better on the tests than those with less exposure.

"We find strong evidence against the view that childhood television viewing harms the cognitive or educational development of preschoolers," write Jesse Shapiro and Matthew Gentzkow in the paper, published this year in the Quarterly Journal of Economics.

There's a big caveat: The testing data are from 1965, because those kids had been around when television rolled out from city to city in the U.S., providing what essentially hasn't been seen in the United States since, a large-scale, clear-cut, before-and-after comparison.

"It's an open question how the ways in which television is different now than then would affect the data," says Shapiro, an assistant professor of economics at the GSB.

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But even with more recent data, another U. of C. economist reached a similar conclusion to that of Shapiro and Gentzkow.

"Despite the conventional wisdom, watching television apparently does not turn a child's brain to mush," wrote Steven Levitt, with co-author Stephen Dubner, in the 2005 hit book "Freakonomics."

They looked at a huge early-childhood study conducted by the U.S. Department of Education in the 1990s and found "no correlation," they wrote, "between a child's test scores and the amount of television he watches."

One of the big questions for economists is not just examining an activity in isolation but considering what activity it replaces.

Psychological research shows that violence in media increases aggression, for example. But "violent crime decreases on days with larger theater audiences for violent movies," another recent study of media effects found. The implication: However aggressive you may feel, you can't do the crime if you don't have the time.

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Violent movies aren't the same as children's afternoon television shows. But Shapiro and Gentzkow also found that much of the impact of the medium they were studying seemed to be related to what activities it might be ...