Early Screen Time May Hurt School Performance, Study Finds

After a few years of teaching, Jordan Friedman, a kindergarten teacher in Boston’s suburbs, can tell which kid gets a lot of screen time at home. “They can’t sit still for a five or ten minute period of time,” she says. Friedman teaches at a school that provides iPads for classroom use. So far, she refuses to use them. 

Her classroom observations echo what researchers are now finding on a larger scale. A new study from several Canadian institutions, including The Hospital for Sick Children in Toronto, followed more than 5,000 Canadian children from infancy through elementary school. They examined how screen exposure in early childhood may influence academic performance years later. 

The researchers asked the parents about how much daily time their child spent watching TV, playing video games, and using smartphones or iPads, beginning at the age of five. “Self-reported data is the most feasible method for privacy reasons,” says Dr. John Hutton, a professor and physician at Children’s Medical Center in Dallas, who was not involved in the study.

While previous studies have already suggested that heavy screen use is linked to poorer school outcomes, this is among the first studies to track children from preschool and measure the effect years later.

“Some kids have no screens at home, while some of them might spend five hours per day,” says Hutton, who has conducted research on digital media use during early childhood. “At this age, the brain is still very plastic, and these early experiences will impact language and emotional skills later on.”

The study found that screen time is negatively correlated with school achievement, with higher screen use linked, on average, to lower standardized test scores. They looked at reading, writing and math skills in grades 3 (8-9 years old) and 6 (11-12 years old). 

Because children at this age often don’t yet receive grades, “we used four levels to evaluate the achievement,” says Magdalena Janus, co-author of the study and professor in the department of psychiatry and behavioural neuroscience at the Offord Centre. “Level 1 indicates struggles in school, while Level 4 reflects excellent performance.” The findings show that each additional hour of daily screen time in early childhood was associated with about a 9 to 10% lower likelihood of reaching a higher academic level in math and reading.    

Kids are going to learn what they practice, according to Hutton. “If they’re reading, they’re going to be good readers; if they’re doing puzzles, they’re going to be good at math.” Beyond missing out on these essential skills, they may also lose opportunities to develop imagination and creativity, Hutton says. 

“There is one kid in my class who, I know, watches a lot of screens at home, and the only thing he ever wants to draw is Spider-Man, because it’s the only thing he has experienced,” says Friedman, the teacher in Boston. “He cannot think of anything else to draw.”

The amount of time children spend on screens matters, but so does the kind of content they’re exposed to, says Hutton. “Some TV shows are developed by teams that include psychologists and educators. That kind of media, such as Sesame Street, tends to be less harmful than others,” says Hutton. However, the ‘educational’ label, often seen on YouTube Kids, for example, doesn’t guarantee good content for children, he says. 

Some programs are designed to help children learn letters or do their first math exercise. “But children need to play, to color, and to interact with their classmates,” says Janus. “When they’re on a screen, the whole world disappears.” 

The surprising effect on girls 

The study found that only a small number of 5 to 7-year-olds were already playing video games, but there were some. What’s surprising is that little girls who played video games seemed to experience a stronger negative impact on later grades than boys. This effect was seen in grade 3, and particularly impacted reading skills.  

Yet, researchers don’t understand exactly why. “Girls, even at this age, can be more addictive and anxious by nature,” says Hutton. Video games involve reward mechanisms, such as scoring points, which stimulate dopamine activity in the brain.

Still, “we saw an association, not a causation,” says Janus. These girls might have struggled in school anyway, for reasons unrelated to video games.  

Parents might wonder, “So, what’s the right screen time limit for my child?” Recommendations vary by country. In France, for example, experts advise no screen use at all before age 3, while in the U.S., the limit is closer to 18 months. 

In his office, Hutton reminds parents that screens will inevitably be part of their children’s lives. “I recommend being mindful of how they’re using it,” he says. “No screen in the bedroom, because they tend to use it more, and avoid screens during mealtimes, bedtimes and homework.” 

According to the doctor, a device shouldn’t be used to calm a child down. “Let them be bored,” he says. “They’re going to use their imagination, maybe grab a book or a puzzle, and learn how to get unbored.”