The end-of-year assignment in teacher Kelly Crits' science class was on the cutting edge of America's energy crisis - to make a model solar home. But the students had to do it using heat-conducting doodads scavenged from home and school.

The North Penn district sixth graders showed up with everything from putty and plastic to a Barbie mattress.

But the students with the hottest house of all built a black-painted cardboard contraption with walls lined in cotton, aluminum foil, and unpoppable bubble wrap. Inside, a floor of gravel, rocks, soil, and water helped retain the heat.

"It reached 116 degrees," said Luke Homan, 12, whose team, the "No Need to Fear the Sun Is Here Co.," built the hottest of 17 houses created by the students.

The activity was part of classes at General Nash Elementary School in Harleysville designed not only to teach students about alternate forms of energy in hands-on ways, but to foster an appreciation of the sciences.

For the teacher, it was also a chance to use techniques polished in a professional development program sponsored by the Merck Institute for Science Education.

The mission of the institute, a division of the pharmaceutical giant Merck, is to foster the kind of engaging, interactive science education that might help grow a future scientist or two, said Margo Bartiromo, director of education programs.

While North Penn has involved its teachers in the institute for 15 years, for the last two a contingent of about 50 district teachers and administrators - including Crits and principal Ron Martiello - have attended its newest program: a leadership academy to create science teams who share what they learn with colleagues.

Teachers and their principals attend a weeklong residential program over three consecutive summers at a Princeton conference center. The challenge for teachers in lower grades is to become proficient in science and feel comfortable teaching it, Bartiromo said.

"If you're an elementary teacher, it's likely you haven't had a strong science background," she said.

For teachers with science experience, the goal is to shake up the status quo.

"Sometimes in education, we get on a treadmill. We're just trying to get things done," Martiello said. "This is about giving students the chance to talk about and make meaning of their world, to debate the evidence."

At the district's York Avenue Elementary School, the enthusiasm fueled by the program inspired one teacher to restart the school's science fair, said Caroline Crew, the district's science coordinator. Another teacher started a notebooking project in which students keep track of moon and sun patterns, and use the record to make predictions and reach conclusions. That teacher shared the project with other teachers who wanted to use it in their classes, Crew said.

Crits has taught solar energy for several years along with other science courses, but her new training, she says, has underscored the importance of using student discussion to connect scientific principles with current events and real-world impact.

Today, she said, her lessons on alternate forms of energy include discussions about the oil spill in the Gulf of Mexico, and coal miners killed in West Virginia.

And then there's the push to invent.

"Instead of Mrs. Crits' telling us to read it and try to visualize it, we actually get to build [a solar house] and see how it can help the Earth," said Tim DiLoreto, 12, of Towamencin.

Inside Crits' classroom last month, students in the throes of solar home construction worked with pieces of foam, newspaper shreds, and bubble wrap strewed across tables. Songs about the sun played on Crits' iPod: Elton's John "Don't Let the Sun Go Down on Me" and Stevie Wonder's "You Are the Sunshine of My Life."

Each of 17 student teams represented a real estate company whose job was to build and sell the solar home. The 17 houses they built then competed in a contest to determine which retained the highest internal temperature for the longest time.

So "companies" including "Zero Kold Inc." and "SunnySide Solar Construction Co." set their houses out in the sun for 20 minutes to see which held the highest temperature the longest.

"No Need to Fear the Sun Is Here Co." won by reaching a temperature of 116 and staying hotter than the competition. The winning team included Homan, Julia Puia, and Billy Brittingham.

Students also used the principles to build individual solar cookers out of pizza boxes, plastic wrap, and newspaper. After a while in the cookers, the lunch buffet included s'mores, bagel pizzas, and hot dogs.

"We learned how we can develop the world," said Brittingham, 12, of Lansdale. "Fossil fuels run out, the sun will be here pretty much forever. If we learn now, it'll be easier in the future."

Contact staff writer Kristin E. Holmes at 610-313-8211 or