A few years ago, Manmadhan and Radha Nair enclosed the patio off their trim suburban house and turned it into a Hindu oasis.

The white-tiled room is a tranquil place for lighting candles, draping deities with garlands and offering rose water and grapes.

They wouldn't have considered such a room 20 years ago. "Honestly, we were kind of embarrassed," said Mr. Nair, 45, who likes to be called Mike. "We were a little worried whether we could expose this kind of thing to other people."

Then their born-and reared-in-America teenage kids came along.

For more than a generation, most of the nation's approximately 1.5 million Hindus--the vast majority of them Indian immigrants--have paid little attention to their ancient faith. Busy building careers and families, they've tried to blend into America. But now the first generation of American-born Indians is coming of age. They are forcing their baby-boomer parents to reckon with a long-neglected faith.

Prayer rooms like the Nairs' are appearing in subdivisions everywhere. Nationwide, a wave of Hindu temple construction is going on; perhaps 1,000 communities are in various stages of planning or construction. About 200 temples have already been built. Devotees are starting Hindu versions of Bible studies and Sunday schools, unheard of in India.

There is a Web site, www.hindunet.org, aimed at the young. And there is a glossy monthly called Hinduism Today that bills itself as a leader in the Hindu "renaissance." On campuses, Hindu awareness groups are popping up. There is even a small organization called the American Hindu Anti-Defamation Council.

What is going on?

"Religion is becoming very important for the second generation because that is the way immigrants maintain ethnic identity," said Prema Kurien, a sociology professor at the University of Southern California. "They first tried to be just American, and they weren't accepted as just American. This is a reaction to that."

But older Hindus are also in the midst of an intense struggle over how to make the religion attractive to their youth. Young Hindus want to know why they should practice the faith, but their parents often don't the answer. Most baby-boomer Hindus learned only the rituals, not the theology, when they were growing up in India.

The Gen-Xers want more. And they, too, are struggling. Those who've learned the faith from their parents want to keep it. But every day they battle against two opposing forces: American culture and their parents' Indian ways.

Some Hindus believe that if they can rejuvenate their faith, it can become an important American force, like Islam. Everyone agrees, however, that the path will be difficult.

Manish Nair, 15, plopped in a chair in his living room on a Saturday afternoon. He wore shorts and a T-shirt but said when he goes to the temple he wears a "juba"--loose-fitting pants and a shirt.

"Religiously, I'm settled," he said. "I'd like to follow Hinduism. But culturally, it's hard. What we do in the home is completely different from what I do out there."

He eats meat outside his house--a practice that goes against Hindu teaching. On the other hand, he doesn't expect to date; it is simply not done in India. And he intends to marry an Indian woman.

His father sat next to him, smiling his approval.

In the early years, the Nairs found it difficult to keep up the daily prayers; they were busy coping with jobs, a young family and the overwhelming American culture. So for a while, they let the rituals slide.

Then the children got older.

"They have pushed us a lot," Mr. Nair said. "We picked up all our knowledge of Hinduism from our parents, and we felt if we were not giving it to our children, a great culture would be lost. It's our moral duty to show them."

Still, the disconnect between the two cultures can be wearying.

"I bring my friends home and they ask, 'Why do you worship elephants?'" Manish said, referring to the god Ganapati, with his elephant face.

Manish hopes Hinduism lasts into the next generation in America--but he isn't sure it will.

That is the anxiety of Hindus. Even though some Hindu families are working to create a vibrant faith in America, many Hindu leaders worry their numbers are small.

Hindu observers worry the faith won't adapt to U.S. culture.

Most Hindu priests are trained only in leading rituals--which don't interest the vast majority of American Hindus, observers say. Most Hindu leaders have no training in teaching, counseling or programming, according to the Rev. Arumugaswami, managing editor of Hinduism Today. He and others believe that an American-style menu of services like classes and activities will draw Hindus.

Hinduism Today recently published an article about the organizing efforts of American Muslims and added an editor's note suggesting that Hindus could learn from those efforts.

In many ways, Islam, which claims about 6 million American adherents, was in Hinduism's situation a decade ago.