Silvana D’Ettorre’s 36-hour journey from anonymous college student to starring role in a presidential visit began with a Tuesday night phone call from the White House.

D’Ettorre, a sophomore exercise-science major at the University at Buffalo, was selected to introduce President Obama at UB, where he unveiled his plan for making higher education more affordable.

The 19-year-old Grand Island native confidently walked up to the podium Thursday morning to address the crowd of 7,200 and the assembled media in a packed Alumni Arena.

“Actually, when I was on stage I was thinking, ‘This isn’t that bad,’ ” D’Ettorre recalled in an interview. “I was really relaxed up there.”

She got a hug and a hearty thank-you from the president on stage and a compliment from him backstage, making for a day she said she won’t forget any time soon.

Her parents, Alan and Rachelle, couldn’t be prouder of their daughter, now in the running as America’s most famous college student. “She did a great job. She looked comfortable and welcoming,” Rachelle D’Ettorre said.

UB officials recommended Silvana D’Ettorre to White House aides to be speaker because she’s a good student involved in a number of campus activities, including a close-knit academic community. But she had no idea she was in the running until she got the call.

She said she immediately accepted, though she couldn’t tell anyone except her parents beforehand.

She researched what other student speakers have said, but she wanted her speech to reflect her own views.

She stayed up until 4 a.m. Wednesday writing her remarks, which UB and White House officials reviewed.

Backstage before the speech, D’Ettorre told Obama she wants to go to dental school. “He said that I should be a dentist based on my smile,” she said. “I told him, ‘I never imagined this would ever happen to me.’ ”

After her presidential embrace, Obama praised her and asked for a round of applause for her parents.

Her brother, Nik, a UB senior, and sister, Sierra, who plans to attend UB next year, also were there.

As the arena cleared out, D’Ettorre said the president’s remarks on the spiraling cost of college struck a chord with her. She said she is taking out some loans, though she doesn’t know precisely how much she will owe when she graduates.

Body copy: “I don’t know if I want to calculate it right now,” she said. “I’m just enjoying my time here and studying hard.”