Girls get better grades than boys in school.

There are also more female college graduates than males.

So, why is there a much smaller number of women in science and technology fields than men?

It could be related to something that happens to girls as early as first grade.

In a recent study, researchers concluded that girls as young as age 6 start to think they aren’t as smart as boys.

Why this happens is still a mystery.

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What the researchers found

Findings of the study were first reported in the journal Science.

According to the authors, the premise for the study was that men, more often than women, are associated with intellect.

This assumption or stereotype is what discourages women from holding successful careers in fields that “cherish brilliance,” such as science, technology, engineering, and math (S.T.E.M.).

“Because of this stereotype, are women less likely to be successful [in the workplace]?” Lin Bian, Ph.D. candidate in psychology at the University of Illinois at Urbana-Champaign, and lead author of the study, told Healthline. “It’s important to know if young girls are being held back because of these stereotypes.”

About 400 children participated in the study, Bian said. About 75 percent of the kids were white.

To conduct the research, Bian and her team put the young students into groups and presented a few different scenarios about gender and intellect.

One of scenarios had the children listen to a story about a “really, really smart person,” Bian said. The researchers never disclosed if the person in the story was male or female.

When the story was finished, they showed the kids pictures of two women and two men, and then asked the kids to identify who they thought the story was about.

At age 5, the children usually selected their own gender. But at age 6 that changed.

Boys were 70 percent more likely to pick a man, but girls were only 50 percent more likely to pick a woman.

Bain said that response was consistent across all races.

In another setting, the researchers showed the children a game and said only “really, really smart people could play,” Bain said.

They then asked the kids if they wanted to play. At age 5, both boys and girls showed equal interest. But at age 6, more girls showed less interest.

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Why the research is important

Matthew C. Makel, Ph.D., director of research at Duke University Talent Identification Program, told Healthline that it’s rare to find researchers focusing on such young children with regard to perception of gender intelligence.

He found the age of participants coupled with the line of inquiry especially insightful because the research is trying to get at the larger implications about the role of women in the workplace.

“I think the questions they are asking are great,” he said. “They should be applauded.”

But he also cautioned against jumping to conclusions so quickly. The particular focus group was only from one community, he added.

“We as consumers of the research need to be careful of the findings,” Makel said. “It’s still an awfully small sample.”

He believes that in order for researchers to make definitive declarations about how young girls view the intelligence capacity of their gender, a bigger, more broadly based study is warranted.

He’d like to see the study replicated in different communities within the United States and around the world. Even better would be to follow a group of children, starting at age 5, and continue to assess their views on intelligence and gender each year.

“To see how individual perspectives change,” he said.

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Still wondering why

Bian and her team didn't ask the kids the reasons behind their choices. That’s for another study currently under way.

But the researchers did discover that the children’s assumptions about their gender had nothing to do with academic ability.

They asked the kids who did better in school. Both genders said girls.

Makel said the children's perspectives about academics are backed up by data.

Girls in general do better than boys in school. Females also consistently graduate from college at a higher rate than males. They now account for 60 percent of all college graduates.

“So they can succeed and excel,” he said.

But good grades and academic achievement don’t always translate into positions of power.

Particularly in work settings where intelligence or brilliance is revered — even demanded — such as S.T.E.M. related careers.

Females make up half of the work force in the United States, but they hold less than 25 percent of S.T.E.M. related jobs, according to a report from the Department of Commerce.

What’s more, women who hold S.T.E.M. degrees are less likely to work in these fields. Instead, they pursue careers in education or health-related industries.

Makel said the answers as to why are complex.

Some studies have shown that women and men choose careers based on different values, Makel added. Men appear to be drawn to jobs or careers that allow them to work with things, he said. Women often lean toward careers that place a high value on building relationships.

“What’s the cause of that?” he said. “Is it biological factors or is it society?”

These are the kinds of questions that this study is ultimately trying to get at, Makel added.

Bain suspects there will be multiple reasons, including influence from parents, peers, and the media.

“We want to find out the reasons,” she said. “The answer won’t be a single reason.”