All month we've been telling you about exceptional high school graduates. A Brooklyn teenager helped to support his family and care for his baby sister, while earning top grades to gain admission to one of the country's best universities. NY1's Michael Herzenberg reports.

Ethan Ambrose is a high school senior who wants to change the world.

"I want to make medical care attainable for anyone regardless of socioeconomic status," said Ethan, who attends Medgar Evers College Prep School.

You might think that sounds unattainable, but meet him and you just might believe it's possible.

"Everybody always said, 'You're smart, you do great things.' But now it's sort of tangible," Ethan said.

Ethan will graduate from his school later this month, second in his class. He got in to Harvard — with a scholarship.

"I called my mom and we both cried on the phone," Ethan said.

He's worked hard, not only in school. Ethan has used money earned from tutoring to pay for groceries and some other household expenses.

And when his single mom gave birth to a girl two years ago, Ethan stepped up again.

He changed diapers and took on other childcare responsibilities so his mother could go back to work and attend college.

"I was really upset at the time," Ethan recalled. "I was saying, 'I had a bright future and now, you know, it's going to become way more difficult,'

"But as I started going on and as things started to settle in, I realized that it was much easier than I thought," he continued.

Caring for his sister, Ethan says, at times meant missing hours of school — at times an entire morning — but the teachers at Medgar Evers College Prep were flexible, and that made it possible.

"This is a very disciplined, committed, and focused individual," said Michael Wiltshire, the principal of the school.

Wiltshire says Ethan is a mentor to other kids and will continue to be.

When he's in college at least, Ethan will have one less worry. 

He's one of 85 kids nationwide to win a Jack Kent Cooke Foundation Scholarship.

All of his expenses will be covered for four years while he works to change the world. He wants to be a pediatric neurosurgeon.

"I just want it to be so that the richest person on the planet and the poorest person on the planet have the same sort of access to healthcare," Ethan said.