A study finds children ages 2 to 4 spent the most time with educational media, averaging one hour and 16 minutes a day viewing TV or using online programs. (Jeffrey MacMillan/Jeffrey MacMillan)

The youngest of children, from toddlers to preschoolers, are the most frequent users of educational media. But as they grow older and spend more time watching television and using mobile devices, they are less engaged with content that teaches math, science and other lessons, according to a study released Friday.

The findings by the Joan Ganz Cooney Center highlight an explosion in the market for educational television and apps aimed at young children — even babies. Thousands of Web companies on the iTunes and Android mobile stores promise to teach even newborns how to spell and add numbers.

Children ages 2 to 4 spent the most time with educational media, averaging one hour and 16 minutes a day viewing television or using online programs, the report found.That average dropped to 50 minutes a day for 5- to 7-year-olds and to 42 minutes a day for 8- to 10-year-olds.

“At a younger and younger age, kids are accustomed to using these tools,” said Victoria Rideout, the author of the report. “Companies see this trend and are creating much more content that is for the very youngest kids and marketing that content as educational.”

But the market for educational apps and television shows shrinks as children enter school, the study found. Distracted by video games and other entertainment online, a generation of school-age children with handy access to smartphones, game consoles and e-readers find fewer options for educational content, according to the report.

The survey of 1,577 parents found that 13 percent of 2- to 4-year-olds use educational activities on a mobile device or computer, but only 6 percent of 8- to 10-year-olds do these activities.

Parents said they believed their children learned “a lot” from educational media, and four in 10 said their children talked about something they learned from educational television shows and learning apps, according to the study.

Television shows still dominate media consumption in homes, but nearly two-thirds of children ages 2 to 10 have access to devices such as e-readers and computers.

The marketing of television programs and apps as tools to turn babies into little geniuses has drawn increased scrutiny by child advocacy groups who worry that parents are parking their children in front of screens at too early an age and for too long.

Child advocacy groups have criticized the toy industry and apps developers for promoting their products as educational with little proof that infants and toddlers can learn any faster with their technology.

The Campaign for a Commercial Free Childhood filed a complaint last year with the Federal Trade Commission , alleging that Fisher Price’s Laugh & Learn Apptivity software falsely promises to teach babies letters and numbers.

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