Imagine a colorful classroom inside the Earth.

That is what the students at Eden Hall Upper Elementary School, Pine-Richland School District, stepped into last week when an Earth Balloon was inflated in the school's Exploratorium.

John Pacay of Earth Adventure, a nonprofit group that offers interactive K-12 education programs, led the fourth-, fifth- and sixth-graders into the 17-foot-high balloon. Satellite images of the Earth are imprinted on 24 panels of durable satin polyester to form a made-to-scale, realistic model of the planet.

One by one, the students entered the translucent Earth balloon through a zippered opening and took their seats on the South Pole. Around them were the blues of the Earth's oceans and the greens and tans of its land masses.

"It's a unique perspective," Mr. Pacay said, to see the Earth's five oceans, seven continents and both poles from one spot. "Kids can easily see the connections.

… It's a 360-degree platform for teaching about the Earth we live in."

Mr. Pacay has been instructing students for eight years since he retired as a teacher and principal in Illinois.

By the time the Earth Balloon's visit ended Feb. 20, all 45 classes at the upper elementary school, along with special needs students, would have had the opportunity to view the Earth model, said Barbara Young, co-president of the Parent Teacher Organization, which sponsored the program that started Feb 18. Earth Adventure's Web site indicated the Minnesota-based organization charges $1,200 per day for the balloon and instructor.

Eden Hall in Richland, which opened this year, was designed with the Earth in mind. Murals and an interior color scheme represent the desert, grasslands, aquatic, tundra and forest biomes. The school's 30-plus acres at 3900 Bakerstown Road are part of the learning experience also. Outdoor "classrooms" include an amphitheater, retention pond and walking trails. Live trees are also planted inside the school.

Mr. Pacay's presentations varied with each class to reflect its science curriculum. Fourth-graders learned about regions of the United States, fifth-graders focused on biomes and ecosystems, and sixth-graders concentrated on earthquakes and plate tectonics.

Mr. Pacay touched on globalization, deforestation, rain forests, global warming, climate change, and the seasons, to name a few topics, during each 20- to 25-minute session.

"You can teach all sorts of things through the lens of geography," said Mr. Pacay, who included math and science in his program.

"Geography used to be memorizing states. Now it's so much more."

Information about Earth Adventure is available at www.earthadventure.org.