LONDON -- At 16, Isabelle Aleksander spends hours writing computer code and plans a career in engineering. Her latest passion is the Raspberry Pi, a low-cost, credit-card-size computer developed to help teach programming.
But when she told her best friend -- "he's male, also into programming" -- his response was not what she had expected. "He was like, 'Wait, how do you know about them? You're a girl and you shouldn't be doing that,"' Ms. Aleksander said incredulously.
She and her friend Honey Ross, 15, are among the few girls at King Alfred School, their private school in North London, with an intense interest in technology. The two, confident and outgoing, say they understand why: computing can seem boring from the outside, populated mainly by nerdy boys.
"It's sad," Ms. Ross said, chatting between classes in the computer lab. "It's such an amazing world. It's kind of waiting for loads of young girls" to jump in.
Belinda Parmar would love to see that happen, particularly since current statistics suggest that women in technology, already a relative rarity, are about to get even scarcer.
Three years ago, Ms. Parmar founded Lady Geek, a consulting firm that helps technology companies connect with female customers and bolster the number of women in work forces. Convinced that the paucity of women in technology has its roots in earlier life, Ms. Parmar last fall started Little Miss Geek, a non-profit aimed at convincing girls that programming is not a solitary grind but creative and eventually lucrative work.
Both sexes love gadgets -- but while girls may enjoy owning the latest devices, parents and teachers do not point out that they also have the brains to build them, Ms. Parmar says.
"They're dreaming of using the iPad mini and the latest smartphone, but they're not dreaming of creating it," she said.
As a consequence, Ms. Parmar said, women are missing out in an industry that is changing the world and growing and paying handsomely, as other sectors shrink.
Britain's technology sector is 20 percent female, according to Eurostat, the E.U. statistics agency; Ms. Parmar cites a figure of 17 percent. Neither is far off the E.U. average of 21.8 percent, or the U.S. rate of 24 percent of technology jobs held by women, down from 36 percent in 1991, according to the National Center for Women & Information Technology, at the University of Colorado in Boulder.
The future looks bleak. Girls take just 8 percent of Britain's computer science A-levels, the high school exam that is the passport to university studies, Little Miss Geek reports. In the United States, girls are 19 percent of high school Advanced Placement test-takers in the field, the Colorado center says.
Ms. Parmar traces the problem at least partly to technology's image. When her team asked children to draw a person who worked in technology, all sketched men, often geeky and disheveled.
That brainy-guys-in-the-garage stereotype is hardly helped by companies that Ms. Parmar believes condescend to female customers with pink devices, and offend them with bikini-clad models at technology shows. "The technology industry is 30 years behind the car industry" in interaction with women, she said.
If they do enroll in computer classes, pre-adolescent and teenage girls often find they are the only girls in the room.
"Even girls that are doing well at math, they opt out. They just want to belong," said Marina Larios, president of the European Association for Women in Science, Engineering & Technology.
Messages about gender and technology tend to start in earliest childhood, when boys are encouraged to play computer games and think about how things work, while girls get toy makeup and fashion sets, Ms. Parmar said.
Catherine Ashcraft, senior research scientist at the Colorado center, said:
"It appears on the surface that women aren't choosing" technology, but "there are a lot of factors that are influencing that choice." She continued: "Girls talk about how even when there's a computer in the house, they don't get access to it as much, because the boys are pushing them away."
Subtle, even unconscious bias can prompt parents, teachers and guidance counselors to give the sexes different study and career advice, she said.
On top of that, those in the field say, computer curriculums on both sides of the Atlantic bore pupils of both sexes with a focus on how to use Microsoft Word or create a spreadsheet. Topics like programming and design, advocates argue, are more likely to engage a generation that imbibed basic skills as toddlers, and to improve Western ability to compete with Asian nations that often give far stronger grounding in such subjects.
Stagnant or declining enrollment in math, science and computing "is a general concern, regardless of gender," Ms. Ashcraft said. "The situation is even more dramatic for girls."
Her center has worked with computing teachers to reach out to groups of girls, rather than individuals, hoping that friends will ease one another's discomfort at being outnumbered in class.
Little Miss Geek runs school workshops and gets women from the industry to talk to students. Ms. Parmar hopes to secure corporate sponsorship to expand the effort with coding clubs for girls and more classroom sessions. For International Women's Day, her team is going to two London schools with iPads, BlackBerrys and female role models.
Some East European and Baltic countries do better than the West. Latvia has the highest proportion of women in programming in Europe, at 33 percent, while Romania has 30.6 percent, according to Eurostat.
That is a legacy of communism, which espoused gender equality, training women as technicians and engineers, Ms. Larios said. Now, "the numbers are declining, and they're finding the same challenges we're finding."
In the developing world, the problem is more severe, said Nigel Chapman, chief executive of the development group Plan International. In many countries, girls lack access to technology after they quit school because of discrimination, poverty or early marriage.
Without computer skills, "they are shut out from one of the weapons to fight poverty," Mr. Chapman said.
"These girls you meet, when you give them access to technology, they lap it up like water," he added. "People want it, they know they need it."
Ms. Parmar sees another opportunity. "Who knows what the devices would be like if women were creating them?" she said. "I'm excited about the future of technology, and I want girls to be a part of it."
This article originally appeared in The New York Times.