Sonia Manzano Shares How Robin Williams Became Her Favorite ‘Sesame Street’ Guest, Despite Ignoring Most of Her Script (Exclusive)

Sonia Manzano is remembering one of her favorite guest stars from her Sesame Street days: Robin Williams, who appeared on the show first in 1991.

Speaking to PEOPLE in an exclusive interview to coincide with the release of a new documentary — STREET SMART: Lessons From a TV Icon — Manzano, who portrayed Maria on the show from 1971 to 2015, spoke about some of the celebrities who have appeared on the show over the years.

“It was thrilling for Robin Williams to be on the show, and I happen to have written one of the Robin Williams bits, and so when it’s aired, I’m very proud to say, you know, ‘I wrote that bit,’ and take credit. But then I say, ‘And you know what? He actually used two words that I actually wrote,’ ” Manzano says with a laugh.

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Williams is famous for improving many of the scenes in which he acted, with Manzano adding that one of her favorite Sesame Street skits with Williams was one titled, “How many things can you do with a stick?”

“You could imagine he was even using it as a mustache for Gene Shalit, who was a film critic who had a huge mustache, so that was wonderful,” Manzano said.

After struggling with an undiagnosed case of the debilitating brain disorder Lewy Body Dementia (LBD), the prolific actor and comedian died by suicide at age 63 on Aug. 11, 2014, at his Paradise Cay mansion in San Francisco.

Manzano worked with a slew of celebrity guests during her time on Sesame Street telling PEOPLE she also has fond memories of iconic musicians. “Stevie Wonder was fabulous, and, you know, he did ‘Very Superstitious,’ and everybody was on the same page. White people, Black people, old people, young people, everybody was rocking to him. And also the people who were famous when I [was younger]: Ray Charles, Tony Bennett. I mean, these were, very famous people.”

She adds: “I knew my time to leave the show was when I stopped recognizing who the celebs were. I called my daughter, I said, ‘There’s this really cute guy on the show, and he’s singing, and his name is Bruno something…’ She said, ‘Mom, that’s Bruno Mars.’ ”

The new documentary STREET SMART, directed by Emmy-nominated filmmaker Ernie Bustamante, traces Manzano’s  journey from the South Bronx to the world of television via interviews, original animation, and reenactments.

Speaking to PEOPLE, Manzano reflected on the enduring legacy of Sesame Street and why it continues to resonate with young and old audiences all these years after its 1969 debut.

“I think that Sesame Street is its own thing, and nothing could compare to it,” Manzano tells PEOPLE, noting that she took many lessons from the show when she created the children’s series Alma’s Way on PBS. “The lesson was: look around and see what kids need at that time. At that time, Joan Cooney [a writer and producer chosen to oversee and direct the creation of what eventually became the children’s television program], said, people who run the world can read. Therefore, these kids… should know how to read, and they were underserved African American children. That was the initial goal.”