Caught between two equally undesirable alternatives—remaining in a difficult situation at home or going out into the city on her own—Kasey was forced into a decision no teen should ever have to make.

"It was because of the way that I am that my mother, you know ... got rid of me—because I'm a lesbian," said Kasey, then 19. Kasey's grandmother took her in for some time, but even that was short-lived: The emotional abuse she experienced there became too much. "I can't be here because it's really tearing me apart … I would rather sleep outside than be here with my family."

Roque's story is different but in many ways the same. And if not for his teacher, Maria Rivera, 17-year-old Roque would likely be out on the streets, too—or worse. "He would say, 'Drop me off at this place,' and it wouldn't be the place they were living the day before," said Rivera, who took it upon herself to look after him. "Then I would start to see him circling—so then I started circling, and I was like, 'He's not going home.'"

"When we offered [a] room he took it immediately, and in front of me he called both parents," Rivera continued. "There was no 'No Roque! Come here [from the parents].' That was heart breaking."

Finally, there's Anthony, who was driven to the streets by an abusive stepfather when he was just 14. "When I came home, [my stepfather] would just take the phone and smack me and be like, 'If you don't like how it is in my house then you can get the fuck out. You don't have to be here,'" recalled Anthony, 18. "Then I would just leave."

The stories of and interviews with these three Chicago teenagers are the centerpieces of The Homestretch, a recent documentary created by filmmakers Anne de Mare and Kirsten Kelly that aims to challenge stereotypes about youth homelessness. The documentary demonstrates the complexity of the issue—a problem that's often hidden from the public eye.

"We were searching for subjects that hit us in the heart," Kelly told me, reflecting on how she and de Mare developed the documentary, which debuts on PBS in April but is already being featured in public screenings across the country. "We found this kid was basically kicked out because he had come out as gay in high school … We started researching and learning over time that there were over 15,000 kids registered in the Chicago public school system classified as homeless and no one was really talking about it."

Since embarking on the project, Kelly and de Mare have realized that the problem isn't only prevalent—it's also growing. By the close of the 2013-14 academic year, Chicago Public Schools had identified more than 22,000 homeless students, which are defined by the U.S. Department of Education as those "who lack a fixed, regular, and adequate nighttime residence." These kids account for roughly 5 percent of Chicago's total public-school student population.

And Chicago's young homeless population is by no means an isolated one. The DOE's latest national survey, which was conducted during the 2012-13 school year, showed that there were 1.2 million homeless students across the country. Moreover, the statistic only includes children officially classified as homeless; the number of students living without a fixed residence is likely much higher.

Where The Homestretch most succeeds as a film lies squarely in its authentic, no-frills portrayal of what it means to be young and homeless in America. It doesn't overload the screen with tear-jerking montages of young panhandlers tethered to street corners, begging cup in tow. Instead, it reveals that, in the U.S., youth homelessness is as subtle as it is insidious—and that disagreements over what "homelessness" looks and feels like, and over the role schools should play in conquering it, have perhaps been the greatest obstacle to finding a solution.

Being homeless as an adolescent or young adult entails more than simply lacking a reliable place to resort to after school. It's compounded by the absence of stability, both physical and mental, at a time when a person is most vulnerable. It's not easy to focus on algebra homework when your nights are spent curled up on a friend's couch counting down the days until you wear out your welcome; imagine cramming for a history test in an overcrowded shelter surrounded by strangers.

Kelly and de Mare wanted to portray the reality of the problem without superficially pandering to viewers' sentiments. "We really wanted to try to show what we were seeing in terms of how much these kids have to move in order to survive," Kelly said. "We were not interested in perpetuating this image of the kid on the sidewalk. That's not what we were seeing."

The Homestretch also delves into the basic logistical challenges faced by homeless high school students. In the film, a local shelter for young people known as "The Crib" is shown turning away the hoards of kids waiting outside nightly simply because it lacks adequate beds. The caretakers call out the names on the list—a homeless draft of sorts—as the teens listen attentively, hoping they are lucky enough to hear their names called. At least half of the kids waiting are turned away, forced to spend the night at a friend's or curled up in a cold city corner. The reality is that there just simply isn't enough space to house all of America's homeless youth: On any given night in the U.S., fewer than 5,000 emergency and transitional-living beds are available for young homeless people to crash on.

* * *

Homelessness rarely exists in a vacuum; it's typically just one of the many challenges plaguing an individual, particularly when that individual is still growing up. On top of showcasing the day-to-day experiences of group of homeless teens, The Homestretch explores issues ranging from immigration to growing up lesbian, gay, bisexual, and transgender (LGBT)—experiences that serve as clues to why certain children end up on the streets.

It also demonstrates that being homeless makes young people much more vulnerable to additional dangers: A 2014 report by the National Coalition for the Homeless showed that, the longer a kid is homeless, the greater the likelihood that child will be physically assaulted, raped, or trafficked. A widely cited 2002 report from the U.S. Department of Health and Services—one of the only reliable data sources for such information—suggests that as many as four in 10 homeless youth have experienced sexual abuse. "One of the things that no one really talks about is that very often when young people run away from home—they are running away from abuse," de Mare told me.

Still, statistics delineating youth homelessness in the U.S. are either hard to track down or narrow in scope, significantly handicapping efforts to address the problem. And the data is sparse in large part because homeless kids often become very adept at dealing with—and hiding—their situations. "Everyone was so engaged in moving forward because that's all they could do," de Mare said. "A lot of these kids, because they have been through so much, know how to process their experiences. It comes out of being a survivor." In other words, these kids' ability to mask their predicaments unfortunately makes it more difficult to alleviate that suffering.

And, as The Homestretch demonstrates, this is where the public school system plays an important role. Every school district in the country is legally required to designate so-called "homeless liaisons" for their campuses. But, as the film reveals, these liaisons are often overworked, meaning it's up to the teachers who go above and beyond their duties in the classroom, filling in as de facto social workers.

"When we started having these conversations with teachers, they said, 'We're in this crisis situation and nobody is talking about it. We are scrambling to try to figure out what to do, there are no resources to really support us,'" Kelly said. "Schools really became the kind of replacement home in these situations ... because it's a place where you have shelter, food, and a bathroom so you can have that kind of consistency."

"But also it's also a place where you go every day, and the teachers were probably the only ones in your life asking, 'Where are you going?'"

Barbara Duffield, a director for the National Association for the Education of Homeless Children and Youth, touted the documentary for exhibiting how integral educators are to helping get their students into stable living situations. "I have [the documentary] ingrained in my mind. I say that because you would think having seen it that often that it would lose its impact, but it never has," said Duffield, who's worked with homeless children for 20 years and saw the movie six times. "Teachers like Maria who are savvy. They really have to be the eyes and ears because otherwise this is population that tries to blend in."

Most teachers probably know the warning signs: A kid starts dropping grades, acting out, wearing dingy clothes, or, perhaps most telling, putting his or her head on the desk first thing in the morning. Still, teachers must tread lightly, even when asking the simple question: 'Is everything alright?' "Adolescents don't want to be different for any reason, especially if it's because they didn't have shoes," Duffield said.

Other advocates, however, worry about the country's over-reliance on teachers to address homelessness. One of them is Daniel Cardinali, who runs Communities in Schools, a national program focused on creating formal support systems for students to ensure that they don't drop out. The organization for its part employs a team of coordinators who work within the schools. They are trained to identify and address homelessness, theoretically taking some of the onus off of classroom educators.

"Teachers are with the kids all day, but they are not trained to understand what's going on, and they are dealing with 30 other students. We don't think it should be left to chance," Cardinali said. "When schools are places of holistic support, we have a really good chance of catching kids when they are in distress. You have a much higher probability of getting to a problem before it becomes really disastrous."

The greatest obstacle, however, isn't necessarily that there aren't enough resources and caring adults to dedicate to these children. It could be the ideological disagreements among federal policymakers about what defines homelessness and what method is most effective in eradicating it.

Absent manpower and resources, state and local governments have largely used a triage approach to address homelessness, ranking people based on their needs. The people in immediate danger—essentially those on the streets who are on the verge of death—are typically deemed "most important." While some believe this is the most effective approach, others fear that there isn't enough attention being paid to the root causes of homelessness; this often translates into a political battle between the reactive advocates and proactive ones.

A new bipartisan bill attempts to bring everyone on the same page, but while some advocates believe it could help, others aren't so sure. The Homeless Children and Youth Act of 2015 would "amend the definition of a "homeless person" under the McKinney-Vento Homeless Assistance Act to include certain homeless children. The McKinney-Vento law was originally passed in 1987 under President Ronald Reagan, and Congress has reauthorized the act a number of times since then, most recently in 2009. The new proposal essentially aims to broaden the Department of Housing and Urban Development's current view of homelessness—one that focuses on the homeless facing particularly imminent risks. Proponents of the bill claim that the department's narrow focus often means that the kids who go from house to house—the floaters and runaways, for example—don't necessarily get the support they need.

But the bill has already garnered a good deal of pushback. Among its critics is Nan Roman, who oversees the National Alliance to End Homelessness and describes the legislation as misguided. Roman and others worry that widening the door could take away resources from the homeless individuals who are most in need of support. "It will include a lot of people who aren't homeless; they would then be competing with people who are homeless for resources," Roman said.

Yet others disagree, and at last week's briefing at the U.S. Capitol, no one was more earnest about the bill's promise than Stephanie Van Housen, a DOE-designated "homeless liaison" in Iowa. In her testimony she told stories of young people in her school district, some of whom are forced to sleep in motels next door to sex offenders."I cannot stress to you enough the importance of [expanding how we identify] who is homeless," she said. "I do not want to have to tell one of my students, 'If you really want help just go sleep under the bridge at the Iowa River.'" In order for many of these struggling teens to qualify for assistance, she emphasized, they would have to be "homeless" in the most literal definition of the word.

The unintended consequence of these debates is that government agencies end up playing a game of hot-potato with homeless teens. Is it a housing-department problem? Or is it a wake-up call for those managing the child-welfare system? Should resources be concentrated among the older homeless people dying on the streets? Or should they instead focus on the younger generations so kids can't get out of the cycle before it's too late?

As Duffield put it: "We need to keep people alive. But I think the bigger issue is that in the last 10 years children and youth haven't been a priority of federal efforts, period."