We'll go into that later, but first the big question: Deep down, do girls and women really believe it? And will they take steps, as they grow, to make high-paying careers in science, technology, engineering and math (STEM) a reality?
New research finds that the answer may be no.
Even when girls say they believe this message, they don't really believe it.
Researcher Pascal Huguet of Aix-Marseille University in France found in 2009 that middle school girls did less well on a math test when told that boys generally did better in math than girls. Even girls who denied they held a belief in girls' inferiority did poorly. Without the negative information, they score nearly as well as men.
Too often, girls just know what parents and teachers want them to say about female math ability. But in fact, by middle school, the cause is already lost for many girls. Stereotype threat--that confidence-killing burden of anxiety--has already set in.
Girls and boys in elementary, middle and high school take math and science courses in roughly equal numbers, and girls perform at least as well as boys. Recently, girls swept the top prizes in the first ever Google science fair.
More good news comes from the Girl Scouts Foundation, which recently reported that girls are now saying they can have a career in STEM. Its study finds that 74 percent of teen girls are interested in STEM and 82 percent see themselves as smart enough to have a career in STEM.
But if those teens look ahead a few years, they could see a horizon that looks ominously more narrow.
Even as college-educated women have increased their share of the overall work force, they hold a disproportionately low share of STEM undergraduate degrees, particularly in engineering.
Women with a STEM degree are less likely than male counterparts to work in a STEM occupation; they are more likely to work in education or health care.
This is important for women's financial futures as well as the country's technology. Women with STEM jobs earned 33 percent more than comparable women in non-STEM jobs.
Rebecca Blank, acting deputy secretary of the Commerce Department, warns that the lack of women in STEM is harming U.S. ability to compete in the global innovation marketplace. A 2011 report from her department finds that while women fill close to half of all U.S. jobs they hold less than 25 percent of the ones in STEM.
Fortunately, there is a window of opportunity we should not ignore. A team led by psychologist Anthony Greenwald at the University of Washington discovered that although girls in the early grades see math largely as a male preserve, they haven't yet made the connection that "because I am a girl, math is not for me."
Learning 'Math is for Me'
So there is a short period of time in elementary school during which girls are relatively open to the idea that they can enjoy and do well at math. They can learn that math is for them.
If they don't, they will never find their way to college-level studies in math and science.
It is a step forward that many girls in middle school today are getting the message that "of course girls can do math and science." But these messages are often way too late. We need to do all we can to help math-and-science girls believe in themselves.
We also need to help them believe that STEM careers are not for lonely male "nerds." Engineering and science are typically collaborative efforts, with teams working closely on complex problems. The image of the socially awkward loner, working alone with test tubes in a dingy lab, is a far cry from reality.
Also, we know that women often look for jobs that have a social impact; where they can do good while they do well financially. STEM offers plenty of that.
Scientific teams drastically reduced childhood leukemia, are saving the everglades, preserving sea turtles in the Caribbean, reducing AIDS in Africa, learning how to save lives by predicting volcanic eruptions and solving crimes through forensic science. This is too often not what girls think when they hear the words "math and science."
We need to adjust that picture.
Boston University journalism professor Caryl Rivers and Rosalind C. Barnett, senior scientist at the Brandeis Women's Studies Research Center, are the co-authors of "The Truth About Girls and Boys: Challenging Toxic Stereotypes About our Children" (Columbia University Press).