The price of Sofia Alfaro's future was a 1994 Chevrolet Camaro.

Her stepfather sold the car when Sofia was 5, paying for safe passage from her native El Salvador to the United States. But that journey led to another - her years-long struggle to learn English and adapt to a new country. She fell a grade level behind her peers due to her limited English skills and was sent to an alternative school - not for bad behavior but to catch up.

And did she.

Now 18, Alfaro is valedictorian of Houston ISD's Young Women's College Preparatory Academy and has accepted a full scholarship to Georgetown University in Washington, D.C. She's among a large number of students once classified as English-language learners who are valedictorians and salutatorians in Houston ISD this year.

It's hard for DeLesa O'Dell Thomas, Alfaro's principal, to talk about her story and accomplishments without crying.

"To know she's overcome challenges in spite of everything else that's going on in the world - I'm just so proud of her," Thomas said. "She overcame the odds, she's going to overcome the odds, and she's going to overcome every challenge that she's going to face."

Alfaro's story also illustrates the complexity of the debate over those brought into the country illegally as children. While Alfaro has been able to continue living in the United States under the Deferred Action for Childhood Arrivals program, an Obama administration measure that bars deportation for those meeting certain conditions, political tensions over immigration have intensified under President Donald Trump. Even Trump has acknowledged that the question of what to do with DACA recipients is a "very, very difficult subject for me" because "you have these incredible kids."

"We're gonna deal with DACA with heart," Trump vowed in February.

'Cannot give up'

For her part, Alfaro has opted to keep her head down, focusing on her studies and her future.

"My family is part of what helped me keep on going," Alfaro said. "I cannot give up, because I want to make them proud."

In the Houston ISD, nearly half of this year's highest-ranking students once struggled to speak English, making them among the largest groups of non-native English speakers to be named valedictorians and salutatorians by the district since 2007. About 44 percent of Class of 2017 graduates were once English-language learners, the district reports.

Generally, such students graduate at lower rates than their peers and typically require more resources and help to succeed in the classroom.

Craig Albers, an associate professor of educational psychology with expertise in English-language learners at the University of Wisconsin-Madison, said that while the high number of non-native, English-speaking valedictorians should be celebrated, the district still has work to do.

"How many English-language learners are dropping out or underachieving? How many have the potential to be scientists, physicians, lawyers or engineers?" Albers asked. "We should celebrate once we know the English-language learners have equitable access to education and everything else."

While Spanish speakers make up the bulk of English-language learners, there are about 100 different languages spoken by students and families in HISD.

Nationwide, about 62 percent of English-language learners graduate from high school, according to the National Center for Education Statistics, but those numbers vary by state. In Arizona, for example, only 18 percent of such students graduated in 2014, compared with 84 percent of English-language learners in Arkansas.

About 71.5 percent of Texas' English-language learners graduated in 2015, according to the TEA, while the Houston ISD saw 73 percent of its ELL students graduate that year.

However, HISD graduates a smaller share of its English-language learners than neighboring districts, according to Texas Education Agency data, including Cypress-Fairbanks, Fort Bend, Galena Park, Spring Branch, Alief and Pasadena ISDs.

Dual language learners

Meanwhile, the number of non-English-speaking immigrant students in HISD keeps growing.

This school year alone, the district welcomed more than 6,000 students who'd moved here from other countries, according to Gracie Guerrero, HISD's assistant superintendent of multilingual programs. Some fled chaotic situations while others were brought by families seeking better futures. But the new students that Guerrero sees have one thing in common: the desire to realize their own American dreams.

"They certainly have that grit and persistence," Guerrero said. "They have overcome these obstacles and have this inherent confidence, because they have a different view of the world, which may not be that of your typical student. They understand and know all of the talents they have and are able to persevere."

She said that if a student succeeds through an effective English Language Learning program, they often perform better than typical native-English-speaking HISD students.

Among the most effective ways to help non-English-speaking students is through dual language schools, which allow them to learn core academics in their native tongues while sharpening their English skills, Albers said.

Guerrero said that about 93 percent of students who go through such programs graduate in the district.

Such schools do more than just ease a student into speaking English, Guerrero said. They show students that their native languages and cultures are valued and that there's no shame in learning a new language as well.Houston ISD has 62 such dual language programs, including one at DeChaumes Elementary, which Alfaro attended years ago.

Alfaro's mother came to the U.S. following the death of her husband, shortly after Alfaro was born. She worked two jobs in the Houston area for several years, sending money back to help relatives care for her daughter and waiting to save enough to bring her to Texas. It was only after Alfaro's stepfather sold his car that mother and daughter could be reunited.

It still took years for Alfaro to fully grasp the language of her new country.

"It was probably elementary and middle school that I got up to speed with my language, because the dual language classes really helped, as well as having ancillary classes taught in English," Alfaro said. "At that moment I didn't think I was learning or growing, but now that I look back I think, 'Wow, I've learned so much.'"

Sets sights on med school

Alfaro's math skills, and the pace at which she completed her studies, caught the attention of her principal at High School Ahead Academy Middle School. She made it her mission to get Alfaro into the Young Women's College Preparatory Academy, which has more than 500 students and a majority of minority students. The academy typically only accepts high-performing middle schoolers and offers a rigorous, accelerated curriculum.

Alfaro now holds a 4.5 grade point average and has completed multiple Advanced Placement courses for college credit. She hopes to go to medical school and study how the environment affects people's health but is humble about her accomplishments. She's soft-spoken and offers a warm smile to strangers and classmates alike. When she speaks of her mother's and stepfather's sacrifices to help her succeed, Alfaro often can't help but shed tears of gratitude.

She urged other non-native English speakers to pay attention to each assignment, as each one is a step toward becoming fluent - and graduating.

"It's not just an assignment, it's an assignment that can help you grow," Alfaro said. "You can learn one single word from one assignment, and those little words just accumulate and at the end you have a vocabulary that is phenomenal. It helps so much."