(CBS) — Oprah Winfrey and the impact of her groundbreaking show is the subject of a new exhibit, “Watching Oprah: The Oprah Winfrey Show and American Culture.” It opens Friday at the Smithsonian’s National Museum of African American History and Culture.

The exhibit features interactive interviews, movie costumes and artifacts from the Oprah show’s 25- year run. Organizers say it examines the ways that America shaped Winfrey, and how her work shaped our country today.

Winfrey, a major supporter of the National Museum of African American History and Culture, wasn’t part of the process of creating the exhibit. “I’m not sure what’s in it,” she told “CBS This Morning” on Tuesday, saying her team led by Amy Weinblum worked with the museum.

“I’m going to see it for the first time today. My team’s been giving up a lot of stuff from the show over the years. They’ve met with most of the producers, and so I think I’m going to be surprised,” Winfrey said.

She acknowledged that it’s a “really big deal.”

“[‘The Oprah Winfrey Show’ has] been off the air seven years as of May 25, and there is not a day that I go anywhere in the world that there aren’t several people who come up to me and tell me about the impact the show’s had on them. And that is no small thing for me,” Winfrey said, adding that she presses the people to tell her the specifics. “Usually I end up saying, oh, I get it. I raised you. Because people tell the story of coming home at 4 o’clock and turning on the TV and watching with their mothers.”

In discussing how she’s proud the exhibit focuses on watching the “The Oprah Winfrey Show,” Winfrey also shared a conversation she had with poet and civil rights activist Maya Angelou.

“Here’s the biggest thing,” Winfrey said. “When I had finished doing my school [Oprah Winfrey Leadership Academy for Girls] and I was sitting in Maya Angelou’s kitchen … and I said to her, ‘Oh, Maya, this is going to be my biggest legacy, the school.’ And Maya says, ‘You have no idea what your legacy will be. Your legacy,’ she says, ‘is every life you touch. Your legacy is every person who’s ever watched a show and made the decision they were going to go back to school, they were going to talk about domestic violence.'”

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