BUILDING THEIR WAY : CHILDREN DESIGN PAPER CITY.

Byline: R.A. Hutchinson Daily News Staff Writer

Children in a summer enrichment program put on their hard hats this week and got out their calculators to design and build Polyhedraville.

The colorful construction-paper city features dozens of geometric shapes rising from a half-dozen separate cardboard bases. A network of streets separates each project area into four quadrants for housing developments, schools, malls and golf courses.

``My grandfather likes golf,'' said Sean Fahey, 9, among five students developing a project area. ``I like miniature golf, too.''

Near the lush green country club, tiny plastic children play in a sandy stretch shaded by a tall, cylindrical building.

``That's the playground. This is our school,'' said Melissa Vermaak, 8-1/2, pointing to her work.

The children are in a four-week program sponsored by the Conejo Valley Adult School. Parents pay all of the costs, Adult School spokeswoman Twila Cook explained, with $175 tuition per child.

Susan Hobert, a third-grade teacher at Acacia Elementary School during the regular school year, said the Polyhedraville program incorporates geometry, mathematics, accounting and teamwork. To begin building, the students - who will be in third, fourth and fifth grades in the fall - developed a cost sheet specifying costs of $26.25 for each square centimeter of construction.

For example, the four sides of a square house, with each side measuring about 26 square centimeters, would cost $2,627.04. But that's not all. The students also had to figure out how much a roof - made from four triangles - would cost.

``We had to figure out how much everything cost. We had little sheets called nets,'' Melissa said.

Hobert said the net sheets were similar to blue prints. Each geometric shape was divided into one-centimeter squares so students could tabulate mock costs of their paper construction.

A pentagon, which cost about $1,300, was the most expensive construction piece they could buy. Squares and triangles were the least expensive.

Children received $25,000 each in mock credit for each to build a single-family home and contribute to a team of four or five children for assigned community projects. Hobert said the community projects include city halls, fire stations, police departments, jails and - at her insistence - schools.

``It's funny, but none of the classes want schools,'' she said, laughing.

Other members of the project team - Aaron Bialick, 9, Lauren Kelsey, 9, and Michelle Baun, 9 - said they ran out of money building a mall on their project site and had to borrow from Sean.

When students borrow, Hobert said, they have to sign a contract on terms and learn about compounded interest.

``It turns into the real world for them,'' Hobert said. ``They learn about notes. They learn about collateral.''

And, of course, the students are learning the fundamentals of geometry. For example, Hobert said the students discovered on their own that two equilateral triangles make one square, and that two squares can make a rectangle.

``I love watching them figure it out on their own,'' the teacher said.

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2 Photos

Photo: (1--Color only in Conejo edition) Brady Lindbergworks on his quadrant of a section of Polyhedraville, a paper city being built by children in a Conejo Valley program.

(2--Conejo edition only--Color) Charles Shattuck adjusts a signal in his part of a construction-paper city that children are building in Thousand Oaks.

Dusty Locke/Special to the Daily News