Transcript for DACA recipients ponder their future as Trump continues to review the program

I want to know your perspective. Reporter: For the past year inside Vanessa Luna's middle school classroom school lessons have taken a personal turn. But your voices matter. Your perspectives are important. Reporter: Because for some old fears have been renewed. Oftentimes when I was little no one asked me what I thought. I think as a teacher I just want to provide a safe space for my kids and for them to be able to know that their voices are extremely important. Reporter: Especially when some of them or their parents could be deported. Hard to learn when you're worried about a mom to be home when you get there, dad will be there when you get there. We tell our kids constantly, if you work hard you can get anywhere in life. However, with having a status as being undocumented, that proves to be a challenge. So we serve sixth through eighth grade. Reporter: It's a challenge teacher miss Luna knows well. She too is undocumented. Her status has been protected for the last five years under president Obama's deferred action childhood arrival program, or DACA. Granting young immigrants Terp permission to stay and work in the U.S. Nearly 800,000 so-called dreamers protected under a 2012 executive order. This is a temporary stopgap measure that lets us focus our resources wisely while giving a degree of relief and hope to talented, driven, patriotic young people. Reporter: But now several state attorney generals are threatening to sue the trump@ administration to end it, arguing the existing policy is simply unlawful, forcing the president to make a decision before next Tuesday. The fates of these dreamers caught in the political crossfire. Among all of these dreamers there are some awfully bad people. Do you think that anyone who comes here underage illegally should become a citizen, pass a law that says that. Reporter: Since taking office president trump has been mulling over the future of the program. Telling ABC news earlier this year -- They shouldn't be very worried. They are here illegally. They shouldn't be very worried. I do have a big heart. We're going to take care of everybody. Reporter: Today vice president Mike pence telling ABC's Jon Karl the president still stands by this statement. Well, president trump has said all along that he's giving very careful consideration to that issue and that when he makes his decision he'll make it, as he likes to say it, with big heart. Reporter: Yet multiple sources tell ABC news the president is leaning toward ending the program. Are you afraid? Yes. Because? Well, even though I have DACA, I mean, I'm afraid for the community. In a situation where the future is so uncertain in this regard, how can you reassure students? Well, I think people can take everything away from you, and I think that's the way that I thought about it when I was growing up. They can take everything away from you. But they can't take what you have in here. Reporter: She was 10 years old when Luna first arrived in New York from Peru on a tourist Visa, afraid and ashamed. Her status would be kept a secret. You grow up hearing all these messages about what it means to be undocumented. And the messages are not positive. Reporter: She would go on to college, a goal that became a family endeavor. Luna would study while her parents would take on cleaning jobs. I mean, my parents took on three jobs to get me through college. You know? We paid for college cash. I didn't get help from the government. Reporter: Then in 2012 with the stroke of a pen president Obama would introduce DACA. That moment when I received it I was finally able to do something with my degree. Reporter: Miss Luna's dream of becoming a teacher came true in 2014, when she joined teach for America. Your eyes smile when you said that. Yeah. It was one of I think the happiest moments. It wasn't until I became a teacher that I realized the power of our stories and huh importa how important it is for people to know. Reporter: Public outcry in support of professionals like Luna growing louder. Marches across the nation called to defend DACA. This week 66 mayors from 29 states issuing a call to president trump to keep the program. The department of homeland security says they are still processing several hundred DACA applications a day, many of them renewals. Like that of Oswaldo, high school senior. He asked us not to use his full name, preferring to keep his case under the radar. There is a possibility right now that the program might be canceled. Reporter: On this day he and his grandfather are seeking the help of an attorney, Cesar vargas. Over the past years vargas has taken dozens of pro Bono case. Your grandparents are really big fighters, and they're fighting a lot. Reporter: An opportunity for him to provide both legal and moral support. They're your inspiration. They're your role models. You're a lawyer. This is your business. But for you this is also very personal. It is personal because I am undocumented. I am protected under DACA. And if DACA is taken away I could lose my driver's license. I could lose my work authorization. I could possibly lose my law license as well. Reporter: Vargas is the first openly undocumented lawyer in the state of New York, the place he calls home. If I was to be deported, I would turn right back because this is my home and no one's going to take me away from my home. Reporter: He was 5 years old when he was brought to the U.S. By his mother. Together they would cross the Mexican border illegally. He says the feeling of uncertainty has been looming long before trump took office. What we're seeing now is a deportation force that president Obama pretty much fueled up and handed the keys to president Donald Trump. Reporter: Referring to the more than 2.5 million people who were deported under the Obama administration. More deportations than any other president in U.S. History. And now that DACA hangs in the balance, he and many other advocates are advising hopefuls to think twice before applying. Especially if they have never applied. If that's the first time the immigration agencies will now have their information. And especially we're recommending against applying if they have siblings who are also undocumented. So your advice then is if you have DACA and it needs to be renewed renew it but if you don't have DACA stay quiet? Absolutely. Because as this point we don't know what immigration will do with any type of information that applicants are going to submit. Reporter: But Luna cautions against retreating into the shadows and says instead it's crucial to raise voices, now more than ever. It's an idea she's teaching her students. Dear Mr. President. Dear Mr. President. I am writing this letter to you -- Because I believe there is an issue you must address. The issue is -- Reporter: In their letters to the president the students' lives are front and center. As an American citizen I feel like we should all be treated the same. Brutality. Climate change. Immigration. I am hispanic. Let's say it was your family. How would you feel? If you could sit across from president trump right now, what would you say to him? That's such a challenging question. It pains me to say this. But I mean, I have no respect for him. And for what he's doing. And I know he's in a position of power, and I know that I would have to be able to persuade him. But why do I have to persuade him of my humanity? Reporter: Humanity and hard choices. Luna is now desperately saving money just in case she's forced to leave the job and the country she loves. There still has to be a sense of hope within that. You have to -- I'm extremely hopeful that the future will be better. And that's what I try to tell my kids. Raise your hand if you've ever struggled before. Reporter: For "Nightline" I'm Byron Pitts in New York.

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