Science and technology are upending how we learn. We separate the science from the snake oil and look at how parents, teachers, and policymakers respond.

When some researchers read a group of five-year-olds a story about a person who was “really, really smart,” and then asked what gender the protagonist was, the girls overwhelmingly picked girls and the boys overwhelmingly picked boys. But by age six, that had changed, with significantly fewer girls picking their own gender compared to boys who still favored theirs, suggesting that stereotypes of men’s “natural” or “innate” brilliance start very young.

The research, published Jan. 26 in Science magazine, also found that by age six—around first grade—girls were more likely than boys to avoid games said to be for children who are “really, really smart.”

Gender stereotypes strongly influence ambition, and career choice. “Brilliance” in men has been used to justify many of the gender gaps that exist in math and science. But the reality is that girls frequently outperform boys in school and out in the work world. Boys drop out of high school at higher rates, and enter college and finish university at lower rates. In fact, girls often even outperform their male peers in elementary school. But stereotypes of who is “really, really smart”—kid-speak for “brilliance”—persist in the face of overwhelming fact, and appear to start very early.

The researchers—Andrei Cimpian, an associate professor of psychology at New York University, Lin Bian, a doctoral student at the University of Illinois, and Sarah-Jane Leslie, a philosophy professor at Princeton University—did four experiments. In the first two, they tried to understand how kids think about brilliance and whether the differences predicted the kids’ interests; in the second two, they tried to detect how the differences affected the kids’ interests.

In the first set of experiments, when children were read the story and asked to pick the gender of the protagonist, girls picked girls 70-75% of the time. The figure was roughly the same for boys. But by age six, girls picked girls only 45-50% of the time, compared to boys, whose figure was relatively unchanged (65-70%).

“The results suggest that children’s ideas about brilliance exhibit rapid changes over the period from ages 5 to 7,” the authors wrote. By first grade, girls don’t favor their own gender when deciding who is “really, really, smart” as much as boys do.

In the second two experiments, the researchers sought to explain the drop in girls’ estimates of their own gender’s abilities. They tested whether it was because the girls thought boys do better in school: children were asked to guess which of four other kids, two boys and two girls, “gets the best grades in school.” The girls accurately guessed that their own gender did better. And yet they still believed the boys were” smarter.”

“Thus, girls’ ideas about who is brilliant are not rooted in their perceptions of who performs well in school,” the authors wrote.

“Girls are already starting to think that doing well at school is a matter of following the rules and paying attention,” says Cimpian. To some extent that’s true, he said, but at the same time, ”they are ignoring objective evidence in front of them when judging who is really, really smart.”

The same held true when the researchers told kids they had a new game to play, one that was for “really, really smart” people, and one that was for people who try “really, really hard.” At five, there were few differences in what girls and boys selected; by six, boys were 64% more likely than girls to choose the game for the “smart” kids.

It is likely that the pivot that takes place at age six accumulates, snowballing into choices to drop “hard” or “brilliant” subjects like math, science, and philosophy, and potentially contributing to fewer women pursuing science, technology, engineering, and math careers.

The results, the study authors concluded, are bleak. “Many children assimilate the idea that brilliance is a male quality at a young age,” they write. “This stereotype begins to shape children’s interests as soon as it is acquired and is thus likely to narrow the range of careers they will one day contemplate.”