"The petting experience — it's wonderful for them. You can tell they get so excited," said Eric Carter whose kids, Kiana and Levi, were among the first to get a sneak peek at the Philadelphia Zoo's new children's area, KidZooU.

"And you don't feel bad about taking them out of school," he said. "It's still educational, you know? Kind of a win-win."

Kiana and Levi were in the outdoor barnyard area Tuesday, busy petting different breeds of goat. Some had hair that was very soft and curly, like sheep. Other had thick, coarse hair, like straw. The fact that they were petting extremely rare goat breeds — including a few of the barely 300 Arapawa goats left in the world — didn't faze the children.

Zoo officials hope children will come for the goats, and stay for the conservation.

Largest learning center among U.S. zoos

Vikram Dewan, zoo president, says the $33 million KidZooU has the the largest learning center of any zoo in the country. The former Pachyderm House, the 1939 stable built for elephants, has been transformed into an interactive gaming area.This is the "U" of KidZooU.

There is a chicken egg hatchery. There's an ant cam, offering the unique perspective of being inside a living ant farm. Another exhibit focuses on the noble character of the rat.

"They are learning empathy, caring," said Dewan. "Children will be able to do what animals do."

The zoo may be focused on animals but the learning center leans strongly toward energy conservation and global warming. A cartoonish domestic tableau is filled with devices using electricity; if children turn off power switches, for instance, they can help save a polar bear. If they stack cereal boxes onto a conveyor belt moving into a recycling truck, they can save a parrot.

Illustrating the results of conservation

"The thought of animals going extinct is a very broad concept," said Dewan. "But if you can tie your everyday behaviors to making a difference so that these amazing animals are there for our children, our grandchildren and great-grandchildren, then that makes it real. And one of the ways to do that is by saving energy."

The KidZooU is the latest, and largest, of a string of projects which Dewan says will bring America's oldest zoo into the 21st century. He is continuing an ongoing project to install 1.5 miles of enclosed trail for animals to roam freely. Visitors can already see some glassed-in and elevated trails where monkeys, goats, and wild cats stroll outside of their pens.

"It's a different experience then people have had with zoos, where they are the ones moving and the animals are still," said Dewan.