Inside America's best high school - a boarding school that costs $53,900 a year and feeds students into the Ivy League

When we stopped by Chase House, a girls dormitory, students were celebrating the birthday of one of the girls in the dorm.

Students from all over the world lived in Chase. We talked to students from Australia, Bahrain, Connecticut, and New York City.

The girls were chatting, some were playing a piano in the room and singing along to songs.

They looked ready to relax after a busy day of school.

But it's not just the culture, studying at Andover clearly pays off when it comes time to apply to colleges.

There's a reason the Harvard Crimson called Andover a Harvard feeder school.

For the past three years more than 20 Andover students have gotten into each of the following top schools: Brown University, Columbia University, Harvard University, MIT, Princeton University, Stanford University, and Yale University.

Despite their highly structured days, and the academic workload, students said Andover felt like home.

The culture at Andover is what's alluring to students, according to Ventre. The way that Andover supports its students is distinct, he said.

When we met with dean of admission and financial aid Jim Ventre he told us that the admissions committee looks for certain qualities in applicants.

Andover seeks students with the characteristics of optimism, social agility, perseverance, and resilience.

It interviews all of the students who apply to get a good sense of their stories, and relies on recommendation letters from parents and teachers to confirm that students can meet academic expectations.

It also reviews standardized test scores from The Secondary School Admission Test and the Independent School Entrance Exam, though Ventre said there is no exact cut off for test scores. Every applicant is their own unique case.

"Not everyone has the same preparation, has the same opportunities, but in the context of where they are from and the opportunities that are available to them, we are looking for kids who make the most of those opportunities," Ventre said.

Speaking of Exeter, the rivalry runs deep. Most people told us it was similar to the rivalry between Harvard and Yale.

On Exeter Geek Day, Andover students dress up in red (Exeter's school color) and dress like "nerds."

Students told us that Andover is typically seen as the more "laid back" of the two schools.

Famous alums from Andover include Former presidents George HW Bush and George Bush. Famous alums from Exeter include Mark Zuckerberg and Gore Vidal.

As he showed us around we noticed that the Andover students style of dress was noticeably laid back. We were expecting to see a bunch of sports coats and dresses, but most students were in jeans, sweat shirts, sweat pants, sports hoodies, or flannel shirts.

There's no dress code at Andover. That sets them apart from other boarding schools which —like rival Exeter — require boys to wear ties. Andover also doesn't have Saturday classes, another difference from Exeter.

He took us to Paresky Commons where everyone gets their meals. We learned that the stir fry is the best item in the dining hall.

Senior David Tsai has attended Andover for four years and is a second-generation Andover student who has his sights set on attending Yale for college.

Tsai confirmed that there is ample opportunity for students to follow their passion.

He told us the course offerings are vast: students can take classes like existentialism, anthropology, architecture, religion, and philosophy.

But he also shared that the school environment, with so many driven students and rigorous classes, can lead to stress.

"When you’re put into a school like this, where the competitive environment brings the best out of you, at the same time, you need to ask yourself everyday, 'What am I doing to make sure that I am okay intrinsically?" he said.

"Mental health here is one of the most important things on campus because the only way for you to show your affection for someone, to love someone else, to build connections and build bonds, is to firstly love yourself."

Elliott told us that the same thing that made Andover great when she attended is true today.

"If you have something you want to pursue and a passion, that is something you will be able to do and find," at Andover, she said.

"I think we attract kids who are really excited about striving for excellence ... and that doesn’t feel scary, it actually feels invigorating."

As for why it is the best school in America, Palfry thinks it has to do with the diversity they are able to attract, thanks to an admissions policy which doesn't take into consideration a family's wealth.

"I do think that the most distinctive thing about Andover's program is the need-blind admissions policy, now in our 11th year," Palfry said. "How you have a morally responsible high school with a billion dollar endowment is when you actually admit kids solely on the basis of their admissions criteria," not wealth, he said.

"Need-blind" is typically phrase used in college admissions, and at schools like Harvard, Yale, and Princeton, which have multi-billion dollar endowments.

But even with generous financial aid for families with demonstrated need, some students at Andover still feel the stigma of being a financial-aid student.

A former Andover student submitted an essay to The New York Times which discussed feeling like an outsider compared to the wealthy students whose families paid full price.

"I don’t think that stigma will ever go away in our lifetimes," he said. "I think the stigma of wealth and inequality is a hugely important American story. That's not going to go away because we're at Andover or because we give someone a laptop, or a class ring, or a prom dress, or a winter coat. But that is something we are super conscious of and that we try and do the best that we can."

After taking their US history class, we went to Palfry's office to talk more in depth about Andover.

Elliot is an Andover alum and Palfry attended rival Phillips Exeter Academy. Both said that the students, faculty, and administrators are what make it a special place.

Most high schools pride themselves on the number of Advanced Placement courses they offer. At Andover, it's the opposite. They offer none, and think it makes students stronger.

"We were one of the founding AP schools in the 1950s," Palfry said during class. "We have decided over the time that teaching to the AP is not the best way of teaching."

Still, many Andover students still choose to take AP exams, meaning they must take additional reading and studying on to their already packed schedules.

The class is taught by head of school John Palfry and dean of students Jenny Elliott.

And It didn't feel like a typical high-school class. Rather than a lecture, the class felt like a rolling conversation between students and teachers. Palfry would ask a question of the class, and students would answer as he probed deeper for answers.

It was a unique experience, with Palfry and Elliot working off of each other. After Palfry discussed some of sources for facts students might use in an essay about Jacksonian democracy, Elliot brought the conversation around to self-awareness about how they process information.

"Some of us are super logical thinkers, so as we respond it just comes out in an organized fashion," Elliott said. "Others of us have a [bunch of different ideas] and we need to impose some structure on ourselves in order to establish coherence. It's important for you know yourselves."

We sat in on a US history class for 11th and 12th graders.

The class was intimate. There were 14 students seated in a circular arrangement and two teachers in the class, making a student-teacher ratio of 7:1.

That seems incredibly low for a high school. In fact, it's a little higher than the 5:1 student-teacher ratio for the entire school. The average class size is 13 students.

For comparison, the average class size at American public secondary schools is 26.8 students, according to the US Department of Education.

This is one of the first things that seems to set Andover apart and why graduates go on to lead successful college careers. The small seminar-style classes mimic the learning environment at many colleges.

At Harvard, the student teacher ratio is 7:1 and at Yale it is 6:1.

Our class was in Samuel Phillips Hall, the building students told us is the most iconic feature on campus. Graduation services happen on the grass in front of the hall.

We started walking toward our first-period class, and learned a bit more about the make up of the student body.

There are currently 1,154 students who attend Andover in grades nine through 12. Of those students, 851 are boarders and 303 are day students.

Students of color make up 48% of the class, 45 countries around the world are represented, and 11.5% of students are internationally born.

Annual tuition to attend the school rivals the cost at elite-private colleges, with boarding tuition running families $53, 900-a-year, and day tuition running $41,900.

But not everyone pays the full amount, a benefit of Andover's more than $1 billion endowment and need-blind admissions policy. More on that later.

We arrived at Andover on a sunny morning in October and were struck by how much the high school resembles a college.

The 500-acre campus was perfectly manicured, and students hustled across the school's quad to get to their morning classes.

Within 10 minutes of arriving on campus, a security guard came over and inquired about who we were and what we were doing, because she had gotten a few calls about our presence. But she was friendly and welcoming, and let us go on our way once she confirmed we had the proper accesses.