(AP) - Scores of young illegal immigrants who have called the United States home for most of their lives are excited by the Obama administration's decision allowing them to stay here legally, but they have a lot of questions. Most important: Is it too good to be true?

How will it actually work? What are the risks or pitfalls?

Still, that uncertainty didn't stop text messages and social networks from buzzing with optimism Friday.

"I started shaking," said Cindy Nava, 23, of Santa Fe, N.M., who received the news in a text while on her way to class at the University of New Mexico. She immediately called an attorney, who confirmed the news.

Nava is a native of Chihuahua, Mexico, who came to the U.S. as a 7-year-old. She wants to go to law school after she graduates with a political-science degree next year, and hopes the policy shift will allow her to work.

Some conservatives vehemently disagree with the new policy, even while expressing compassion for illegal immigrants who were brought to the country as children. They say Obama's unilateral action by executive order deliberately skirts the law.

Young illegal immigrants acknowledge they could be at risk if Republican presidential challenger Mitt Romney is elected and decides to reverse the policy.

Renata Teodoro, who came to the U.S. from Brazil when she was 6, says she plans to apply for a work permit, anyway.

"We've been putting ourselves out there for a long time so we are willing to take a chance," said Teodoro, 24, leader of the Boston-based Student Immigrant Movement who has led vigils and organized illegal immigrants from around the country. Teodoro's photo is featured on the cover of this week's Time Magazine along with that of other young immigration activists.

For many young illegal immigrants who have long wished to stay in the country and work without fear of deportation, President Barack Obama's announcement Friday is like a dream come true.

"When I heard the news today, I said, 'Oh my God. Finally, justice has come,'" said Ricky Campos, a 23-year-old college student in Maryland who was brought to the U.S. illegally from El Salvador when he was 12. "I couldn't stop screaming. I can't believe this is happening. I think that finally President Obama has heard us, and he believes in justice as much as we do."

Gaby Pacheco, 27, is an illegal immigrant from Ecuador who has been an outspoken advocate for the DREAM Act, legislation that would carve a path to U.S. citizenship for those who qualify. Multiple attempts to get the measure through Congress have failed.

Pacheco said she hopes the new policy means she'll finally be able to pursue a career working with autistic children.

In the U.S. since age 7, Pacheco has a bachelor's degree in special education and associate degrees in early education and music.

She's been making ends meet by doing tutoring work as a private contractor, one of the few ways people without legal status can work.

"My biggest desire and dream is to work with autistic children," Pacheco said. "I've been feeling empty for the last couple of years because I haven't been able to fulfill that dream."

Pacheco was one of four students who walked 1,500 miles from Miami to Washington in 2010 to bring attention to the DREAM Act.

"I think this is a testament to the power that our community has, that together when we set ourselves to do something, it can be accomplished," she said.

Some of Pacheco's peers are not so confident.

They have questions about how the new policy will work and worry it won't go far enough to protect them from deportation. Some are dismissing it as a meaningless election-year stunt.

"This is politics again," said Dulce Guerrero, a 19-year-old activist who was one of several students arrested last summer in Atlanta while protesting the plight of illegal immigrant youth. "They're just trying to win the Latino vote."

Under the administration's new plan, illegal immigrants will be immune from deportation if they are under 30 and brought to the U.S. before they turned 16; have been in the country for at least five continuous years; have no criminal history; have graduated from a U.S. high school or earned a GED; or who have served in the military. They also can apply for a work permit that will be good for two years with no limits on how many times it can be renewed.

Jonathan Perez, 24, said the latest announcement isn't enough to move him or six other activists out of an Obama campaign office in Los Angeles where they have been holed up since Thursday.

They're demanding an executive order to halt deportations of young people who would be eligible for the DREAM Act if it passed.

The biggest problem with Obama's latest announcement, Perez said, is that students will need to identify themselves to immigration authorities - with no guarantee they'll get a work permit.

"We want something that is actually going to stop all of our deportations," said Perez, a native of Colombia who lives in Montebello, Calif.

He said immigration authorities don't consistently follow a directive issued last year to focus more on serious criminals when making decisions about deportation, and worries the new policy is equally vulnerable.

Perez said he and others will continue protests at Obama campaign offices across the country until the president issues an executive order ending deportations for those who would qualify for the DREAM Act.

"We're going to stand here and make sure they can't come to our community trying to get votes ... while they continue to deport millions of people," he said.

Many Republicans, including former Arizona Senate President Russell Pearce, chief sponsor of the state's 2010 immigration enforcement law, said the administration is making an unconstitutional end-run around Congress. Currently president of the Ban Amnesty Now group, Pearce characterized the change as a "backdoor amnesty."

"The effect is just the destruction of the rule of law," Pearce said. "It's a slap in the face to those who come here legally."

Jan Barton is a citizen activist in Georgia who has been a strong supporter of the state's tough law targeting illegal immigration. She said she is disappointed by the new policy.

"I have compassion for those children that are here illegally, but this amnesty sends a message to all that it is OK to break the law," she said. "Millions of Americans are unemployed, and giving job permits to these people will take jobs away from Americans."