About 160 middle school girls brewed lip gloss, built bridges, and manipulated fiber optics last week - just like professional engineers.

For the 10th summer, Rowan University offered hands-on "Attracting Women Into Engineering" workshops aimed at dispelling stereotypes about the field and boosting the profession's female representation, which has stagnated nationally.

"We teach them it's not all about hard hats," said Kauser Jahan, a professor of civil and environmental engineering, who started the workshop in 1999 with 20 girls.

Unlike other fields of study, where men and women receive about an equal number of bachelor's degrees, just 18 percent of the nation's undergraduate engineering degrees went to women in 2007 - the smallest share since 1996, according to the American Society for Engineering Education.

That trend worries the industry and frustrates academics.

As baby boomers retire and technology evolves, demand for engineers will grow, said Doreen Nixon, director of systems engineering at Lockheed Martin Maritime Systems & Sensors in Moorestown.

"We're going to need more than males," she said.

Teachers continue to worry that girls' interest in science and math wanes in middle school, when "being smart" may become less fashionable, which is why so many workshops are designed for that age group. Drexel University, Widener University, and Lockheed Martin also offer programs for high school students.

But even girls committed to taking four years of science and math in high school courses "haven't gotten the message how they might apply them for careers," said Barbara Bogue, associate professor of engineering at Pennsylvania State University.

"You've got a bunch of kids who are enthusiastic and very capable," Bogue said. "You need environments that are welcoming and supportive."

In testimony to Congress last week about recruiting women into science, technology, engineering, and mathematics, Bogue stressed raising teachers' expectations of girls; improving ways to evaluate existing programs, such as summer workshops; and recruiting female role models.

"Students see teachers or nurses as part of their daily lives, but they may only get to talk to an engineer at a special camp or workshop," said Jessica L. Snyder, a senior engineer in advanced materials at Dow Chemical Co. in Spring House.

Rowan's School of Engineering has a female dean, and eight of its 32 teaching faculty members are women. It offers small classes with hands-on projects, maintains an active Society of Women Engineers chapter, runs numerous teen workshops, and sends mentors to schools for students in high school all the way down to kindergarten.

"We're doing all the things suggested," said Linda M. Head, associate professor of electrical and computer engineering.

Yet female enrollment has hovered between just 12 and 20 percent since the school opened in 1996, said Steven Chin, associate dean. Last fall, it was 16 percent.

Stereotypes are a huge hurdle, women engineers say.

Asked to draw a picture of a scientist, elementary aged-girls often sketch someone with wild hair wearing a lab coat and a pocket protector, said Alisa Clyne, assistant professor of mechanical engineering at Drexel, where the fall's incoming engineering class is 20 percent female. "That's not me," she said.

"People tend to think engineers are very isolated and spend a lot of time working by themselves," said Lockheed Martin's Nixon. In reality, "they are very involved in teams."

Jennifer Kadlowec, associate professor of mechanical engineering at Rowan, jokes that the profession needs the engineering version of workplace dramas CSI, House, and Law & Order. "Engineers don't have a TV show. We're not glamorous."

Women tend to gravitate toward environmental, biomedical, chemical, biological/agricultural, and industrial engineering, according to the education association. Computer, mechanical, and electrical engineering have the smallest percentages of female graduates.

Statistics for the female engineering majors at Rowan, Drexel, and Penn State bear out those national trends, spokesmen said.

"Women tend to be motivated by helping others," Clyne said.

Some drop out of engineering classes they find too abstract or focused on math and analysis, Clyne said. They're more interested in building a car that will slow climate change or developing products to improve health in the Third World. They use the biology- and chemistry-related disciplines as an entree to medical school.

Brighid Burgin, 19, of Mantua, said the Rowan middle-school summer workshop taught her that "engineering was about more than crunching numbers; it was about humanitarianism."

The sophomore chemical engineering major credited a clean-water experiment there with helping her choose Rowan over the six other universities that accepted her.

"We purified water from the Rowan pond and talked about resources around the world," said the graduate of Clearview Regional High School in Mullica Hill.

This summer, she is studying Spanish in Costa Rica with the goal of working on a project with the university's Engineers Without Borders chapter and eventual employment abroad.

Women engineers tend to take more leadership roles in campus groups such as Engineers Without Borders and professional societies, Bogue said. Yet on the job or in the classroom, they still suffer occasional discomfort being "the only woman in the room," students and professionals said.

Rowan chemical engineering senior Eileen Batten of Galloway decided her career path at age 10, largely inspired by her father and three brothers, who are engineers.

She was surprised to be the only woman in her freshman chemistry for engineers class, she said. It was difficult until the men realized that she could hold her own.

"You need to accept the fact that you may be the only female in a room full of men," Nixon said. "But that's where the hard part ends. Brainwise, they can do it."