Gather the kids, they'll likely know who this guy is. He's their champion and a champion of science too. Reporter: Before they even got the chance to hug their parents, some were hugging him. The most... See More
Gather the kids, they'll likely know who this guy is. He's their champion and a champion of science too. Reporter: Before they even got the chance to hug their parents, some were hugging him. The most famous face in the crowd at lehigh university's graduation. And it's a relationship with the next generation he started building 20 years ago. Bill nye, the science guy. Bill nye, the science guy. Reporter: The science guy, the children who learned about volcanoes. About the science behind what happens to your heart, flying with the blue angels. About why you really cry from onions. The tears! Reporter: Turns out, those children have not forgotten who they learned from. Oh, my god! You're bill nye, the science guy. Reporter: We were with him not long before we were taking photos for his fans. When I talk to the camera, i do my best to talk to one person. I'm talking to that kid I want to influence. I want him or her to get excited about this thing that I am so excited about. Reporter: He was inspired by his own parents, his father a japanese prisoner of war. Four years captive. Creating a sun dial to keep track of time in prison. He would cast a shadow through it, and brought back his interest in sun dials with him and it faskted me. Reporter: His mother a great INFLUENCE TOO, A Ph.D. SHE WAS A Code breaker and their son would go to cornel, an engineer for boeing, before becoming the science guy. He showed us his bow tie and this one, the one with the human genome on it. Given to him by the scientists who mapped it. But though ties began in high school, wearing them as a waiter to impress the girls. And then as with everything, a discovery. The bow tie does not slip into your soup. It does not flop into your flask. Reporter: Recently at the white house science fair, when i asked about the photo with the president. The president got to meet me. It was very good for him. Reporter: But in front of the graduates, one thing he wasn't joking about. You all know more science this einstein, isaac newton. Reporter: And about those handshakes. After giving his speech, he leaned over and asked the dean, the president, if he could shake every graduate's hand. All 1,889 of them. As I say to everybody, i don't think they are going to remember what I said, but they will remember how they felt, how they feel at that time, and that is very important. Dare I say it, change the world! I really feel that way. Everybody can make the world better.
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