Roberta Flack knows a little bit about schools. And in conversation it becomes clear that playing gigs like the one she's got coming up this week to benefit the Cleveland School of the Arts is more than just another performance. Before she had the performance career that brought the world hits like "Killing Me Softly with His Song" and "The First Time Ever I Saw Your Face," she was a teacher.

She had developed classical listening habits in her early teens and won second place in a statewide competition for black students in North Carolina by playing Scarlatti sonatas. So, by the age of 15, she had landed a full scholarship to study piano at Howard University. Then she faced a challenge that is familiar to just about anyone who studies music.

"When I got ready to graduate I needed a job and I didn't know what to do. The dean suggested that I take a couple of teaching courses so that I could do that. My first teaching experience was in an all-white school in Chevy Chase, Maryland. It was a very long time ago. We had not yet confronted our various and sundry fears about relating to each other as different races. I enjoyed my teaching experience and learned a lot from those children. Those children had far more world experience than I in terms of travel.

So, in a way that most pop stars could never dream of, she can tell stories from the trenches. "One time I was student-teaching seventh graders about how a symphony is designed. I chose Smetana's "The Moldau,' which starts with flutes like little streams of water and builds bit by bit until the whole orchestra is playing the incredibly beautiful monstrous symphony. As I narrated all this, and my mentor was encouraging me, and the kids were raising their hands, and I was telling them how it all comes together, with all the brass and woodwinds and percussion and strings, and here's the big theme, the big river. And this one boy with his hand raised is about to die to get my attention, so I called on him and he said, "Ms. Flack, that's the Jewish national anthem.'"

While she was still teaching, she began to take jobs as a performer - first accompanying opera singers, then playing for Sunday brunch in "a little gay bar on Capitol Hill." She held jobs at several junior high schools around Washington, DC, but at one in particular, Banneker Junior High, she found that she couldn't teach kids music because they didn't know how to read. Her answer was to use popular music. Long before she was a performer, she used "The First Time Ever I Saw Your Face" to teach three-part harmony to a group of seventh-grade girls.

"You could see it in their faces - they wanted that. They wanted to do James Brown and the Temptations and all those songs that are from their culture," Flack says.

She saw the strength of music to illuminate other subjects and to help kids want to learn. "One of the things I find interesting to share with students is how connected science and all the things we discuss about the music are related or can be related to music in some fashion."

Flack taught at schools for almost five years before her performance career became steady enough to leave the classroom behind. But after a Grammy and 18 albums, she never really did. She's selling her 1914 Mason & Hamlin Model A piano, which appears on the cover of her first album, to benefit the Roberta Flack School of Music at the Hyde Bronx Charter School in Bronx, New York. The school serves disadvantaged children and accepts all interested students at no cost. It's no surprise that someone with this background has strong feelings about education.

"We still don't make it a priority. There are some changes - like the advent of charter schools much like the one I'm associated with - that can make education a beautiful thing at a high level for free. You can't beat that. But I think public schools don't get the attention they need on a regular basis."

Roberta Flack: 7 p.m. Saturday, May 17, at John Hay High School Auditorium, 216.421.7690.