In Tara Guber's ideal world, American children would meditate in the lotus position and chant in Sanskrit before taking stressful standardized tests.

But when she asked a public elementary school in Aspen, Colo., to teach yoga in 2002, Christian fundamentalists and even some secular parents lobbied the school board. They argued that yoga's Hindu roots conflicted with Christian teachings and that using it in school might violate the separation of church and state.

Portrayed as a New Age nut out to brainwash young minds, Guber crafted a new curriculum that eliminated chanting and translated Sanskrit into kid-friendly English. Yogic panting became "bunny breathing," and "meditation" became "time in."

"I stripped every piece of anything that anyone could vaguely construe as spiritual or religious out of the program," Guber said.

Now, more than 100 schools in 26 states have adopted Guber's "Yoga Ed." program and more than 300 physical education instructors have been trained in it.

Countless other public and private schools from California to Massachusetts — including the Aspen school where Guber clashed with parents — are teaching yoga.

Helping kids focus

Teachers say it helps calm students with attention-deficit disorder and may reduce childhood obesity. The federal government gives grants to gym teachers who complete a teacher training course in yoga.

"I see a lot fewer discipline problems," said Ruth Reynolds, principal of Coleman Elementary School in San Rafael. Her observation of the school's six-year-old yoga program is that it helps easily distracted children to focus.

"If you have children with ADD and focusing issues, often it's easy to go from that into a behavior problem," Reynolds said. "Anything you can do to help children focus will improve their behavior."

In 2003, researchers at California State University, Los Angeles, studied test scores at the Accelerated School, a charter school where Guber sits on the board and where students practice yoga almost every day. Researchers found a correlation between yoga and better behavior and grades, and they said young yogis were more fit than the district average from the California Physical Fitness Test.

Guber, married to former Sony Pictures Entertainment CEO Peter Guber, embraced yoga after moving to California in the 1970s. Their 13-acre Bel-Air estate includes a clifftop garden leading to a Yoga House retreat.

In 2004, Americans spent almost $3 billion on yoga classes and retreats, books, DVDs, mats, clothing and related items. About 3 million American adults practiced yoga at least twice a week in 2006, more than doubling from 1.3 million in 2001, according to Mediamark Research.

Exercise or religion?

Despite mainstream acceptance, yoga in public schools remains touchy. Critics say even stripped-down "yoga lite" goads young people into exploring other religions and mysticism.

Dave Hunt, who has traveled to India to study yoga's roots and interview gurus, called the practice "a vital part of the largest missionary program in the world" for Hinduism. The Bend, Ore., author of "Yoga and the Body of Christ: What Position Should Christians Hold?" said that, like other religions, the practice has no place in public schools.

"It's pretty simple: Yoga is a religious practice in Hinduism. It's the way to reach enlightenment. To bring it to the west and bill it as a scientific practice for fitness is dishonest," said Hunt, 80.

"I've talked to too many people who got hooked on the spiritual deception of yoga. They come to believe in this and become enamored with Hinduism or eastern mysticism," he said.

Concerns about yoga's spiritual implications have also fueled a cottage industry of books and videos that offer the purported benefits of yoga — flexibility, strength and weight loss —without mentioning the y-word.

Laurette Willis, 49, wrote an exercise regimen called "PowerMoves Kids Program for Public Schools." The stretching routine includes pauses for children to contemplate character-building quotes from Martin Luther King Jr., Emily Dickinson, Harriet Tubman and William Shakespeare. Willis, who lives near Tahlequah, Okla., also created an exercise regimen called "PraiseMoves: The Christian Alternative to Yoga."

"I'm not here to say that yoga is necessarily bad, but it is counter to what I think the public education system is for: It should have programs without any form of religious overtones whatsoever," Willis said.

The dispute confuses some yogis, particularly Westerners who say they yoga as it's practiced in the United States is primarily about fitness and stress relief.

Baron Baptiste, who owns three studios in the Boston area and practices with his 7-year-old son, loves Guber's program. He said his son takes yoga far less seriously than he does.

"We adults need to be reminded to lighten up, breathe in the joy and have some fun," he said.