Amazon CEO Jeff Bezos came to Seattle’s Museum of Flight today to talk with students about the decades-old rocket engines he rescued from the sea – but he stayed to share some down-to-earth lessons for life on this planet.

“Be proud, not of your gifts, but of your hard work and your choices,” the billionaire told more than 100 kids and grown-ups who crammed themselves into the central gallery for “Apollo,” the museum’s new exhibit focusing on the 1960s space race.

The highlight of the show is a display of components from the mighty F-1 engines that powered Apollo astronauts on the first leg of their journey to the moon. Bezos backed a multimillion-dollar effort to recover the Saturn V engines from the bottom of the Atlantic.

Today, he stood between those artifacts and an intact F-1 engine, which was lent to the museum by NASA, as he answered questions from elementary-school and middle-school students.

Bezos recalled how he had been inspired at the age of 5 when he watched Apollo 11’s astronauts take humanity’s first steps on the moon in 1969. That sparked a passion for spaceflight, and once his Amazon retail venture took off, he founded the Blue Origin rocket venture to follow through on that passion.

“You guys will find that you have passions, and having a passion is a gift. … You don’t get to choose them, they pick you. But you have to be alert to them, you have to be looking for them. And when you find a passion, it’s a fantastic gift for you, because it gives you direction, it gives you purpose,” Bezos said.

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If you get the chance to follow that passion, “all your work won’t feel like work to you,” Bezos said.

Bezos said the Apollo space effort, and particularly the effort to create engines capable of sending astronauts to the moon, exemplified the kind of passion and persistence that he aspires to. He noted that NASA’s rocket engineers “blew up so many engines” in the course of developing the F-1.

“Over and over they would fail, but they persisted,” Bezos said.

During the Apollo missions, NASA used 65 of the F-1 engines, five at a time on each first stage of a three-stage Saturn V rocket. “There was not a single failure,” Bezos said. “That’s the result of all that persistence and hard work.”

Bezos said Blue Origin was working on what he called a “better engine” – the BE-4, which has only about a third of the thrust of the F-1 but is designed to be reused rather than thrown away. The BE-4 engine is destined to power Blue Origin’s New Glenn rocket, which could begin sending payloads into orbit and even onward to the moon in the 2020s.

Earlier this week, Blue Origin reported that a set of BE-4 engine hardware was destroyed during an engine test, but the company is persisting.

One student asked how Bezos kept himself motivated when times got rough.

“If I’m stressed about something … the stress goes away the second I take the first step of identifying the source of the stress,” he replied. “Why am I stressed about this? What’s going on? And then, talk to somebody about it. Find allies.”

He put in a strong pitch for a teamwork approach to solving problems, rather than relying on the “Tony Stark movie version” of a lone genius.

“In real life, you have to work as part of a team to build incredible things,” Bezos said.

Super fun morning talking rockets with a very cool group of students. Great questions. Thx to all the students and to @museumofflight! https://t.co/adXbn3bdon — Jeff Bezos (@JeffBezos) May 20, 2017

Bezos’ account of how the F-1 engines were recovered from the bottom of the Atlantic in 2013 sparked several questions from the kids, but the billionaire confessed that he had no further underwater expeditions on his agenda.

“I’m putting all of my pioneer exploration energy into Blue Origin,” he said.

When one student asked him whether he was always so intense about his passions, Bezos recalled his days in grade school.

“The Montessori school teacher told my mom that I wouldn’t switch tasks,” Bezos said. “They got me to switch tasks by picking me up, including my chair, and just moving me to the new task station. I’ve gotten a little better about that over the years, but task switching is still a problem for me.”

When it comes to Blue Origin, his prime focus is to reduce the cost of access to space by developing fully reusable launch vehicles. Bezos said lowering the “price of admission” for space ventures will open the way for innovations as transformative as those enabled by the internet.

“I wish that there could be a bunch of entrepreneurial startup companies doing amazing things in space,” he told the kids. “You guys, and people your age, are the ones who are going to benefit from reusable rockets. You’re the ones who are going to come up with those creative, entrepreneurial ideas in space.”

Blue Origin aims to be in on that entrepreneurial frontier. Bezos has already proposed using the company’s New Glenn rocket and a lander called “Blue Moon” to send payloads to the lunar surface.

“For a long time, hundreds of years, thousands of years, the idea of going to the moon was so impossible people actually used it as a metaphor for impossibility,” he said. “And then, in the 1960s, we humans did it. What I would hope you take away from that is that anything you set your mind to, you can do.”

Bezos recalled the words of Wernher von Braun, the German-born architect of the Apollo-era space program. Referring to the moon landings, von Braun said, “I have learned to use the word ‘impossible’ with the greatest caution.”

“I hope you guys take that attitude by your lives,” Bezos told the kids.

Read more: Apollo rocket engines fill a place of honor