A series of studies reported in the July issue of Archives of Pediatrics & Adolescent Medicine suggests that the less TV kids watch, the better off they are. In a study of third graders, researchers found that children with a television in their bedrooms had lower scores on standardized tests while kids with access to a home computer had higher scores.

U.S. households with children have an average of 2.8 television sets and 97 percent of those households have at least one video cassette recorder (VCR) or DVD player.

More than two thirds of households with children have at least one computer and more than half (53 percent) have home Internet access. While substantial evidence exists to show that people who use media more heavily are at greater risk for obesity and aggressive behavior, the relationship between media and academic achievement is less clear, the researchers suggest.

"Looking at the media environment in spring 2000, students with a bedroom television scored significantly lower on all the tests compared with their peers without bedroom television sets." the authors write.

"Those with home computer access scored higher on all the tests than those without access. When we simultaneously considered bedroom television and/or home computer access, we observed significant differences for each standardized test. Consistently, those with a bedroom television but no home computer access had, on average, the lowest scores and those with home computer access but no bedroom television had the highest scores."

In a separate study, researchers from the University of Otago, Dunedin, New Zealand, found that children who watch the most television during childhood and adolescence may be less likely to finish school or go on to earn a university degree.

In the study, information about the viewing habits of about 1,000 children was collected at ages five, seven, nine, 11, 13 and 15.

Information on the highest level of educational attainment was collected for 980 of the study members (96 percent) at 26 years of age. Childhood television viewing was calculated based on viewing hours per weekday reported at ages five to 11. Adolescent viewing was calculated based on weekday reported viewing at 13 and 15 years of age.

"The results of this study indicate that increased time spent watching television during childhood and adolescence was associated with a lower level of educational attainment by early adulthood," the authors write. "These effects were independent of intelligence, family socioeconomic status, and childhood behavioral problems."

Researchers from the University of Washington, Seattle, conducting a third study concluded that TV viewing before the age of three may have adverse effects on subsequent cognitive development.

Their analysis used data from the National Longitudinal Survey of Youth 1979 Children and Young Adults (NLSY-Child). It involved comparing scores in mathematics, reading recognition and reading comprehension from a commonly used and well-standardized test, with the level of television watching before age three and from ages three to five.

"This analysis has shown a consistent pattern of negative associations between television viewing before age three years and adverse cognitive outcomes at ages six and seven years," the authors report. "The inclusion of extensive controls for parental preferences, ability, and investment in their children's cognitive development suggests that these associations may in some direct or indirect way be causal."

"By contrast, this analysis suggests that television viewing at ages three to five years has a more beneficial effect, at least for the outcomes of reading recognition and short-term memory," the authors write.

The researchers found no beneficial effect on mathematics outcomes or reading comprehension, and they state, "Because reading recognition and short-term memory are arguably the most basic of the cognitive outcomes studied, the implication would seem to be that the net effect of television viewing from a population perspective is limited in its beneficial impact."

In conclusion, the authors write, "Television viewing in early childhood varies depending on age; for very young children the effects are negative, while for preschool children they can be constructive, at least in some domains.