Despite all the attention being paid to tech and diversity, the gender gap in computing is getting worse.

That bit of unwelcome news—and a call to action to triple the number of women in computing by 2025–comes from Cracking the Gender Code, a new report from Accenture and Girls Who Code. “The attention to coding has popularized computer science among boys, but it hasn’t moved the needle with girls,” says Reshma Saujani, who founded Girls Who Code in 2012 to help close the tech gender gap.

The report concludes that without a broad-based strategy that sparks and sustains girls’ interest in computing from middle school through college, the percentage of women in computing will fall from 24% to 22% in 2025. That’s already a big drop from 37% in 1995.

That gender gap not only impacts women’s career prospects and financial lives, but the U.S. economy as a whole. Keeping women on the sidelines means more computer jobs will go unfilled, reducing innovation and global competitiveness. It is already happening: In 2015, there were 500,000 new computing jobs to be filled but fewer than 40,000 new computer science graduates.

So what’s holding back progress? A number of things. Getting more girls into computing courses is a necessary start, but it is not enough. Saujani says developing curriculum with girls’ interests in mind and teaching in ways that girls prefer—such as project-based work—is needed to keep them engaged.

Reshma Saujani, founder, Girls Who Code, with a class

Reshma Saujani, founder, Girls Who Code, with a class

Crucial, too, is doing more to address the cultural and social stereotypes that are still keeping girls–and sometimes parents–from seeing themselves as excelling in tech. Role models matter. Parents’ attitudes matter. Female teachers also have a positive impact on girls. The endless attention paid to male tech stars isn’t going to change how girls feel about tech. What will inspire them are the stories of women like mathematician and computer programmer Ada Lovelace, of Silicon Valley tech pioneers (here’s a roundup from Backchannel) and women succeeding now in the industry (know a teenager who uses the Clue app? Tell her about founder Ida Tin). “We have to tell stories that will interest a 13-year-old black girl in Georgia,” Saujani says.

The research—one of the few on the subject—included a large-scale survey of girls aged 12–18, undergraduate college students, and industry leaders to understand the state of girls’ interest in computing at each stage of their education.

For girls, interest in computer science peaks in middle school. Then comes the high school trap, when even those girls who enjoyed coding in middle school can lose interest. “The scary thing is that if it isn’t done right in high school, you can turn girls off forever,” says Saujani.

Among the report’s recommendations:

In middle school. Parents and teachers need to show girls that computing is fun and not just for boys, giving girls hands-on experience, for example, with computer games designed for girls. Girls are 18% more likely to show interest in computing if they’ve been exposed to it in their junior high years.

In high school. Not having a friend in a computing class can reduce by 33% the likelihood of a girl studying the subject once they get to college. Summer camps for high school girls can help both those girls who do take classes and those who are swayed by peers. About 81% of high school girls who studied computing over the summer were interested in studying it at college, versus 52% who only studied computing at school.

In college. Schools and professors should encourage women to major or minor in computer science, but also broaden exposure to coding for undergraduates in all majors though campus and summer immersion programs. More than half the women working in computing did not major in computer science in college.

For Saujani, the report ups her desire to increase her own advocacy and share data and ideas to help bring more women into tech. About 40,000 girls have learned coding at one of Girls Who Code’s afterschool camps or summer immersion programs, and Saujani’s focus is continuing to scale the program while helping shape the conversation. As the report makes clear, it is time to follow the progress of the past few years with concrete, strategic solutions or another generation of girls will be left behind.