- [Michelle] It's become his second home.

(bowl bangs) - Thank you.

Ladies and gentlemen, good afternoon.

- [Students] Good afternoon.

- [Michelle] Nearly 20 years after David Upegui graduated from Central Falls High School, he returned to his alma mater to teach science.

- But before we do, let me ask a question.

Krista.

- They have a very unusual eye color.

Could that be related?

- Yeah, you guys remember when we talked about people that have jaundice?

Could this be related to jaundice?

- [Michelle] His Medical Interventions class is a favorite among students.

- Oh, is this something that's progressively getting worse?

Is this some kind of progressive disease?

Good question.

- [Michelle] He begins each class by showing them a picture of a medical phenomenon and has students ask questions about it to try to figure out what caused it.

- Is this related to what's around it?

Good.

Let me go right across here.

- Is this person in a coma?

- Can this person see?

- Are they dead?

- Are they dead?

- [Michelle] After 10 minutes of nonstop questions, he reveals to students what they're looking at.

- But here's what happened.

This was a punch to the head that caused this man in Austria to actually have a star.

- [Michelle] He says it's an exercise in getting students comfortable with asking medical questions.

- When students ask questions, it is a way to recognize that they're engaged, but that they're also thinking deeper.

- [Michelle] Upegui wants his students to be problem solvers.

That mindset informs how he teaches.

- Just so you know, you have eight weeks left of school.

- Yay!

- What would you say is your teaching philosophy?

- My approach is that in front of me are the future stewards of the Earth.

They are going to inherit an Earth, a planet that is hotter than it's been since humans have been around.

It's an overpopulated planet, a planet with political turmoil, with wars, with famine, with huge ecological issues that need to be addressed.

I see what I do as empowering these children to solve those issues.

Because whether we like it or not, that's the planet they're getting.

How do we represent that if we're doing Mendelian problems?

- [Michelle] Upegui has received numerous educational accolades, including the Outstanding Biology Teacher Award for Rhode Island and the Presidential Award for Excellence in Mathematics and Science Teaching.

But teaching wasn't the career path he initially envisioned.

- I went to school for biology and psychology.

But the universe figured out a way to bring me here, back to the same classroom where I stood and learned as a student.

- His interest in education began after his oldest son Isaac was born with Down Syndrome.

- And I thought, I need to take a class in education so I can help this young man have a fighting chance.

I know very little about our public school system and I know very little about special needs and learning.

So I took one class and one became two, two became four.

Next thing you know, I'm sitting with a teaching certificate.

- [Michelle] In 2010, he was working as a data manager at Brown University when he heard that all of the teachers at Central Falls High School had been fired.

The news quickly spread across the country.

- Just last night after the kids in one school kept falling behind, the teachers were fired.

- [Reporter] All 74 teachers at Central Falls High School in Rhode Island were called out by name and fired.

- [Michelle] Upegui decided to leave his well paying job at Brown University and pursue a career in teaching.

- My pay cut was about $35,000 a year.

And I still, even 13 years in, I still don't make what I was making when I left there.

- Any regrets about that?

- Not at all.

None at all.

Heterozygous.

And hetero means different.

- [Michelle] He says his job as a teacher is to help students realize their potential.

- And one of the things that I always tell my students is the universe is not stingy with talent.

We can make the world better.

We can not only learn from it, but we can change it.

We can manipulate it and create a society that's more fair, more just, more equitable.

A parent that doesn't have a dominant can't pass it down.

- [Michelle] And students say Upegui walks the walk, giving them opportunities they otherwise wouldn't have had.

- I did participate in a week of medical school at Brown and that was an opportunity he opened up to me and that was an experience where I got to learn from doctors and students from the Brown Medical School.

- I feel like in that class I can really get out of my comfort zone and speak up in class and with him, it's like there's nothing you can't do and I feel like you really need that.

You really need that optimism.

- Even if it's hard, you can do it.

You can do it.

Take your time.

- [Michelle] Students in Central Falls or CF as they call it, are quick to point out Upegui has taught them a lot more than science.

- He makes it fun to be honest.

I don't know if you guys would agree on that.

- Like if you're panicked, he knows to makes you calm and stuff, and not to worry about everything.

- Yeah, like he's not gonna sit there and just talk the whole time and you're just there waiting for him to finish or whatever.

He makes it engaging.

- You guys got this.

- [Michelle] It's that engaging approach and his ability to relate to others that students say sets Upegui apart as an educator.

- So what I wanna do is I'm gonna give you about five minutes, work collaboratively to do page one and two and we'll stop right there.

- For many of the students in your classroom, you know what they faced because you faced it when you were that age.

- Absolutely.

- How does your own upbringing inform how you teach?

- They understand that I'm from CF.

I know what it was like to have those challenges.

And if you had asked any of us in 1993 when I graduated, what do you wanna do?

I think the answer would've been get out of CF.

But what we were really saying was not I want to get out of CF, what we were really saying and we didn't know how to pose it which is I don't want to be poor anymore.

- [Michelle] Upegui was born in Colombia.

He remembers watching the violence unleashed by drug cartels in the eighties.

His parents divorced when he was young and soon after his mom, a teacher, lost her job.

He found himself homeless as a child.

- One of the first real memories that I have is sleeping on the floor of a bus station.

And my older sister, who's always been my rock, not letting me sleep on the actual floor, but sleeping on her.

- [Michelle] His own upbringing has made him well aware of the struggles of others.

He knows some of his students are homeless.

He buys snacks for them every week.

But it reminds him of a promise he made to a mentor before he became a teacher.

- Promise me that you won't take the work home with you.

You do what you can, but you can't lose yourself in the midst of it.

When you turn the lights off in the classroom, leave the things there.

You can't solve everything for everybody.

(trumpet playing) - [Michelle] It's one of the many reasons why music has been healing for Upegui.

He sings and plays the trumpet for his band, Infusion Evolution.

He describes it as a mix of Afro-Cuban, flamenco and jazz.

(David Upegui singing in Spanish) - [David Upegui] Our music has sort of a rhythmic pattern that allows for people to sway and move.

When people are tapping or moving or nodding their head, that's when you know it's working.

(David Upegui singing in Spanish) - [Michelle] He encourages students to pursue hobbies outside of school.

- I've been really blessed to to play music with these gifted musicians and I get to just enjoy their company and we tell dad jokes and we play music, we get to create.

So that outlet has been tremendously important for me because it's oftentimes that one part of my life where I can be completely creative without the constraints of systems.

- [Michelle] But even in the classroom, he's found ways to be innovative.

He started the school Science Olympiad team and is the first person to teach AP Biology there.

- This is the evidence wall.

When I tell my students, you can do it, I say, yeah, here's the evidence, right?

- [Michelle] The front of his classroom is filled with photos of every AP Biology class he's taught.

- Maria Jose Escobar, who went to Tufts.

This is Aura Hernandez who works for Save the Bay.

- [Michelle] Every picture tells a story.

- This is this year, so this is my period two class right here.

Yeah, these kids are great.

So many of them.

- [Michelle] Over the years, Upegui has shared countless stories with his students, but he says it was a story about how he finds purpose in them that left a lasting impression on one particular student.

- And then she went on to say that, "I want you to know that the day you told that story, I was going home to end my life, but I didn't because of you and you saved my life and countless other people's lives.

You just don't know it."

And I thought, "Wow."

It was just one of those times where I thought, yeah, nevermind the $35,000 a year that I got less, you know?

Nevermind the long hours, because that was worth it, right?

Being able to see a human being and for them to recognize that they belong, that was just powerful.

- Last year, Rhode Island PBS named Upegui to a class