At 1 p.m. Monday, Rocio Hernandez Perez and 29 other young people will walk in a convoy across the bridge over the Rio Bravo and head for the Nuevo Laredo border crossing between Mexico and the US.

Dressed uniformly in graduation caps and gowns in the style of American students, which most of them once were, they will present themselves to U.S. border guards on the Texas side of the crossing and in effect beg to be arrested.

They expect to be handcuffed and removed into a side room in the Nuevo Laredo border post for processing. If all goes according to plan, they will then be taken into detention where they will be held in custody for what could be several weeks.

Monday's action at the Nuevo Laredo crossing is the latest in a burgeoning protest movement organized by Dreamers – the largely Hispanic, undocumented immigrants who were brought to America when they were in their infancy. The mass presentation will be the largest such event yet, following last month's group infiltration of a detention centre in Arizona by nine young activists calling themselves the "Dream Nine".

All 30 of the Laredo activists have spent most of their lives in the US, speak fluent English, and feel themselves to be fully American. Yet all of them have been forced to live outside the country, five because they were deported from the US and the remainder because they were made to feel so uncomfortable and frustrated by growing hostility in their home states that they did what Mitt Romney, the 2012 Republican presidential candidate, suggested and "self-deported".

Now they have had enough and want to come home. "Our hearts belong to the U.S.," said Perez, 23, who lived in North Carolina since she was moved there by her parents at the age of four. "They tell us that's a place where we legally don't belong, but we can't keep quiet anymore. We have decided to take the matter into our own hands, to do whatever it takes to get back."

With political moves for comprehensive immigration reform stalled in Congress, the hope that a pathway to citizenship will be found for the 11 million undocumented immigrants living within the US have begun to fade. And with it, public expressions of anger from a community that has traditionally kept its head beneath the parapet have started to mushroom.

Marco Saavedra, one of the Dream Nine activists who lives in New York, says the mounting foment is a reflection of a generational shift among immigrant communities. The tendency of the older generation to hide in the shadows, in the hope of remaining undetected, is switching to a much more outward approach of the Dreamer generation.

"Younger activists are coming of age," he told the Guardian. "Our parents made great sacrifices, but our generation are not prepared to be taken as second-class citizens. We have been educated in the U.S., have been assimilated, we're not prepared to be treated like that any more."

The activists have been gathering close to the Laredo crossing over the last few days, and have received briefings from the Dream Nine activists who preceded them about what to expect once they enter the border post. All of them previously lived in the U.S., and are now going to ask for asylum so they can return.

Of the 30 expected to take part in Monday's action, four are younger than 18. All of them are of Mexican origin, other than Sandra, 31, who has traveled all the way from Peru. She lived in the U.S. for 13 years but left for Peru after she found her undocumented status was hindering her college education and search for a job.

Perez had similar frustrations that eventually forced her to "self-deport". She arrived in North Carolina in 1994 speaking no English, but she taught herself the language and excelled at school.

The first blow came when she turned 16 and started to learn to drive. She got all the way to the driving test, but was turned away because she was told she had to have a document proving she was a U.S. citizen.

"At that point everything changed for me," Perez said. "I thought I would be able to go to college, and live my life fully as an American, but then I realized it wasn't going to happen."

When she began applying for college, she fell into a Catch-22: as an unauthorized immigrant she would not be eligible to claim public schools' in-state tuition fees which are substantially cheaper. But when she applied for scholarships to pay the exorbitant out-of-state fees, she was told she was equally ineligible for those.

Her parents were very upset for her and encouraged her to go back to Mexico. "They wanted me to get a good education, be able to drive without being stopped all the time by the cops because I didn't have a licence. They didn't like seeing their kid treated like a criminal."

So Perez did go back to the family town of Vera Cruz, in Mexico, four years ago. But it hasn't panned out as she and her parents expected.

"The last four years have been difficult," she said, in an understatement. First, she found it difficult to communicate as she wasn't used to speaking Spanish all day long.

Then, she was shocked by the violence in Vera Cruz. She had expected a level of corruption, but nothing like the ferocious internecine fighting between the drug cartels.

"We hear people shooting each other just a block away. We see pictures of bodies being dumped on the TV, women being raped and their body parts strewn over the city."

One of the worst parts is also the most ironic: the fact that she felt permanently scared because she was seen as an American. She has an American twang when she speaks Spanish, and that carries a danger: people assume she must be rich as she came from across the border.

The risk of kidnapping for ransom hangs over her – even now as she prepares for Monday's border action. Organizers are being careful to accommodate the 30 activists as they await the Laredo crossing in secure houses, away from public attention, so as to avoid drawing attention to themselves and their "yanqui" accents.

But the imperative that is pushing her on more than any other is a simple one: she misses her family and feels terribly alone. As a result, even though she is only five months away from graduating in Mexico, she has decided to drop everything and try and battle her way back into the US.

"Even though I am about to get a good degree in Mexico, I know I am never going to be happy here. I need my parents. I haven't seen them for four years, and I want to go home," she said.

Finally, she is driven by the sense that what she is about to do is far bigger than herself, bigger than all of them. Having felt alone for so long, she now feels part of something.

"Last time it was nine, this time it is going to be 30 of us. How many will it be the next time, and the time after that – how many more are going to come? This is only the beginning." © Guardian News and Media 2013