The girls launched rockets, drove solar cars and snapped pictures with homemade pinhole cameras.
They braved the afternoon heat and collected beakers full of Chesapeake Bay water to test nitrate and phosphate levels. Then they laid gray tarps over chairs and spritzed them with food coloring to simulate pollutants dribbling down a mountain into our water supply.
It was definitely a hands-on week for the 40 area middle-schoolers who attended the SciGirls camp at the Maryland Science Center.
Three female scientists at the center, Katie Stoffer, Lauren Bartelme and Mary Anter, designed the program. "For me, it's an issue of motivation and interest. I wanted to show them what opportunities there are in science," said Bartelme, who manages a space program at the center and has a degree in physics.
The Maryland Science Center hosts a variety of camps every summer, but this is the first one aimed strictly at girls. The camp's founders say they hope it will become an annual event, because the need is acute.
"Jobs in technical fields are expanding at three times the rate of other professions," said Tom Buckmaster, President of Honeywell Hometown Solutions, who sponsored 20 of the campers, "yet the number of students pursuing this is declining in the United States."
Young people from many countries, including Singapore, China, Korea, Japan and Hong Kong, routinely outperform American middle-schoolers on math and science tests, the U.S. Department of Education has found.
American girls fare even worse. They often lag behind the boys in elementary school, and the gender gap widens in middle school, when more girls start opting for courses in English, psychology, foreign languages and fine arts instead of math and science.
"If you scratch it a little bit, science is as cool as anything gets. We just need to do a better job teaching it," Buckmaster said.
To help diversify the group of SciGirls, Honeywell offered need- and merit-based scholarships to the camp, with additional support coming from the Baltimore City Foundation.
Chelsea Williams, 13, from Loch Raven Middle School was ecstatic when she found out she was a scholarship recipient. Her award letter arrived neatly rolled up in a pink beaker with a ribbon. "That was cool," she said. "It made me feel special."
The point, Bartelme said, is to get girls excited about science.
Chelsea, who plans to study chemistry because she likes to mix things, said, "I know sodium and chloride make salt, but I have a lot of other questions."
She also found SciGirls' hands-on approach effective, "It's much easier to learn this way," she said.
For Heather Nix, a rising eighth-grader from St. Agnes School in Baltimore, who wants to pursue chemistry or biology, being surrounded by female scientists was as exciting as the projects she worked on.
"It's been great to have them," she said. "You can really talk to them and ask questions."
SciGirls also invited outside female scientists to speak, including an astronomer, a structural engineer and a scientist from the Johns Hopkins Applied Physics Laboratory.
One of Heather's inspirations was camp counselor Miah Johnson, a chemistry and biology major at Bowie State University.
Johnson's role models were limited - she will be the first female scientist in her family, and she never attended a science camp.
"Their passion for science is growing here," Johnson said of the girls, "and they've gotten to know each other. We've got a diverse group, from Catholic schools and from the inner city, here."
"These camps are probably one of the best ways to get girls interested in science," said Christianne Corbett, a research associate at the American Association of University Women Educational Foundation. "Research shows as women do hands-on activities, it peaks their interest," she said.
Efforts to encourage young women to pursue math and science have been moderately successful.
Of students earning undergraduate degrees in engineering in 2001, 20 percent were women, according to the National Science Foundation. The same year, less than 40 percent of bachelor's degrees in math went to women.
The SciGirls' organizers hope to change this. "One of the things we hope is that these girls will start a relationship with the science center," Bartelme said. The center will invite them to events through the year and encourage them to volunteer as Science Center interns.
Not all the SciGirls want to be scientists, but the seemingly endless opportunities that they discovered did not escape any of them.
"I want to be an interior designer," said camper Maria Laureno, 13, from Mount View Middle School in Howard County. "But they tell us learning science helps you get jobs, and so I'm interested in it for that."
"I might become a chemist or a fashion designer," said Chelsea Williams, the scholarship winner, "because I like colors as much as I like chemicals."
A girl has to keep her options open.