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Girl, father at PACES meeting

Family members discover the world of optics through the University-sponsored PACES program.

When physics is a social science

Physics teachers make scientific curiosity a family affair

By Deane Morrison

April 18, 2008

Curtains barely hold back the early evening light in the Marcy Open School lunchroom. At the tables, children squirm with anticipation as they and their parents listen to laser-wielding physics teacher Nancy Bresnahan. "Can you see light as it passes through space?" she asks. Bresnahan aims the laser at the back wall, instantly lighting it up with a bright red spot. But the light streaming from the laser to the wall is invisible. "No," comes the answer. Then another physics teacher sprays fog into the room, and suddenly a straight red beam can be seen piercing the cloud. "How about now?" asks Bresnahan. The room erupts with oohs, ahs--and yesses. The families take a moment to reflect on the behavior of light they've just witnessed, then it's on to an exploration of how light produces images. So begins a typical encounter between families and physics in PACES (Parents and Children Experiencing Science), a program of the President's Initiative on Children, Youth and Families at the University. Run by high school physics teachers, it brings parents and children together to ask scientific questions, predict how simple experiments will turn out, and then see the results for themselves. The most important thing is that the parents exhibit scientific curiosity for their children. This was the driving factor for University physics professor Cynthia Cattell and Bresnahan, a teacher at Hopkins High School, in obtaining seed money for PACES. "We wanted parents to model the behavior we wanted to see. Parents manipulate the equipment, and kids do, too. They interact as families," says Bresnahan. This night at Marcy Open in Minneapolis, Bresnahan is joined by three other PACES teachers: Jon Anderson (Centennial), Claire Hypolite (Edison), and Louise Weldon (Tartan). All are performers in the Physics Force, a group of physics teachers--including Cattell--who regularly perform entertaining physics-based stunts for young students.

"My goal is to ultimately go into a school, church, or mosque about four times a year, until everybody is not only comfortable with doing science, but looking forward to it."

But while the Physics Force shows kids the joy of physics, PACES has them experience it for themselves. The PACES team stages programs of 45 to 60 minutes in metro-area schools whose students have the most need for scientific stimulation.

Picture this

Each family at Marcy Open has an incandescent lamp in front of them. When turned on, light from its filament will pass through a lens, then a tiny pinhole in a sheet of aluminum foil (poked out by the children). Light that makes it through the pinhole will hit a cardstock screen. Now, the teachers ask, when you switch on your lamp, how will its light pass through the pinhole and project an image of the filament on the screen? Will the image be rightside up, upside down, or what? Talk about it with each other. It's a risky moment; no one wants to guess wrong. But the four teachers stress that being wrong is a great way to learn. When everybody has had time to make a prediction, they switch on their lights and watch as images of the U-shaped filaments appear on their screens--upside down. "What happens when you move your screen?" asks Hypolite. The families move their screens nearer or farther from the pinhole and watch the image shrink and expand. When they move a stick from top to bottom across the pinhole, its shadow on the screen moves too--but from bottom to top. The wonder of it isn't lost on young Isabel Olson. "I was surprised how the image moved and how it changed when you put the pinhole in front of it and when I moved the stick," she says. The families add more pinholes, producing multiple images. But when they move their screens just right, the images merge; they have just created, and focused, a rudimentary camera. What happens when they cover half the lens? They still get a nice, sharp image. "It raises more questions than it answers," observes Theresa Wolf as she works on the experiment with her husband and two kids.

Still plenty of growing space

This was one of more than a dozen programs the teachers have presented to about 200 families in 2007-08, the first year of PACES. At every one, they not only teach but pass out information to encourage students to keep up with school. One brochure describes the Power of You program, which sponsors two free years at area community and technical colleges for qualifying public high school graduates in Minneapolis and St. Paul. But for Bresnahan, there is still much to be done to reach all the students who could benefit from extra help in science. For one thing, PACES presents its programs in the evening, when families--or at least parents--are usually tired. Better to aim for daytime and weekends and catch families when they're already being sociable. "I think to really reach the people we want to reach, we should go into churches or mosques," she says. "My goal is to ultimately go into a school, church, or mosque about four times a year, until everybody is not only comfortable with doing science, but looking forward to it." In setting up PACES, "it seemed to me families were a key, and we have to get the kids early." PACES already draws a diverse mix of people, including Hispanic and Somali families. It helps that Hypolite speaks Spanish and that Gladys Torres-Skendi, an Edison math teacher who also belongs to PACES, is a native speaker of the language. One of Bresnahan's favorite moments came when an elderly Spanish-speaking woman arrived at a presentation by herself. "She wandered in and asked for equipment [to perform the experiments]," Bresnahan recalls. "What a wonderful sight, an elderly woman doing science."