GREYBULL - After a month of classes, Greybull Elementary School students know their new building is special, but opinions differ on what sets it apart.

Some kids say it's the solar-powered lights; others say it's built with recycled cans. They're partly right, and they will be hearing a lot more about the new energy-efficient, green building over the course of the school year.

Completed last month, and just in time for the new school year - or perhaps not quite in time, depending on whom you ask - the $8 million project is the only school in Wyoming based on Leadership in Energy and Environmental Design standards.

Created by the U.S. Green Building Council, the LEED rating system is a set of voluntary specifications for the design, construction and operation of energy-efficient and environmentally friendly buildings.

While the new school's lights aren't solar-powered, there are 26 skylights and 135 windows designed to maximize daylight and cut down on the need for artificial light.

Building materials, while not made from recycled cans, are sourced whenever practical from nearby suppliers and sustainable resources.

"What sets it apart, aside from how efficient the building is, is also how high-tech everything is," said Principal Coley Shadrick.

When escorting a visitor into his previously empty office, Shadrick pointed out how the lights turn on automatically and the room's thermostat wakes up and turns on the heat.

Infrared sensors in each of the 37,000-square-foot building's 27 rooms put them in "dormant" mode when they are empty, Shadrick said.

Moving in wasn't without its challenges, as contractors raced to finish everything from testing room sensors to completing the kitchen and cafeteria to paving the road in front of the school.

Shadrick said the shake-out process included rooms that wouldn't heat or cool properly and other glitches, but after a month in operation, the building is performing well.

"We had a community walk-through and had a great turnout. A lot of people wanted to see it because this is the first LEED building in the state," he said.

When planning the project, school board members traveled to Colorado to visit a LEED school. Last week, school administrators from Belfry, Mont., were visiting Greybull to learn about the project.

Shadrick said the school is a hit with the 235 students in grades K-5, and discipline problems are way down since the move to the new building.

"I don't know why, but the behavior is better. It makes a huge difference," said kindergarten teacher Paula Heuschkel.

"It's such a clean, nice place to come to work. There's so much light and fresh air. The kids like to be here," she said.

The old elementary school building, built in 1919, was regularly described, by teachers and students, as "stinky." Despite the best efforts of maintenance workers, it had leaks large enough to require plastic wading pools to catch the drips.

"The difference here is that most of the rooms are a lot roomier and bigger," said fifth-grader Samantha Stewart, who said she liked the higher ceilings and brighter hallways in the new school.

"The skylights help us learn better than when we were 'locked up,"' Stewart said, referring to the old building.

Fifth-grader Justin Bachus went to a Colorado school last year.

"We didn't have near as many cameras there, and you had to turn on the lights instead of self-activating lights," he said, referring the 23 security cameras at Greybull Elementary.

"Also, the salad bar here, you get to choose what you want on your salad, instead of throwing away all the waste of what you don't want to eat," he said.

Lessons about waste, efficiency and recycling will be built into daily experiences for the students, Shadrick said.

The school will recycle plastic, paper, glass, cardboard and metal, even serving as a community drop-off point for anyone's recyclables, he said.

Shadrick said it is too soon to know exactly how much the building's many energy-efficient features, including a ground-source heat pump and high-performance window glass, will save on energy costs.

But with early estimates putting the annual heating and cooling costs at roughly $13,000, he expects the final number to be a big drop from the $60,000 a year spent at the old school.

"There's a buzz about this place, and I think this building has created a kind of positivity that's catching. It's just a breath of fresh air," Shadrick said.