The Chicago Sinfonietta, known as one of the nation’s most racially diverse classical orchestras is expanding its renowned educational outreach program from elementary and middle school students to the high school ranks.

The SEED program?”Student Ensembles with Excellence and Diversity?”is an offshoot of the Sinfonietta, bringing professional and classically trained musicians together with high school students in master class workshops. SEED, now in its pilot year, is a spinoff of its Audience Matters program for elementary and middle school students.

“The purpose is to introduce these kids to classical music, and to tell them who the important composers are, and how an orchestra is put together,” said Jim Hirsch, executive director of the Chicago Sinfonietta.

The orchestra itself was formed in 1986 by founder Paul Freeman, who today serves as the orchestra’s musical director.

Chicago Sinfonietta, which celebrates its 20th anniversary this year, has instructed middle school students through its Audience Matters program over the years, mainly focusing on Chicago students who play in their school’s band or orchestra.

Audience Matters was the first student outreach program, which is funded by private donors, as is SEED. More than 50 students are involved in SEED at participating schools.

Four of those schools are in Chicago, including Lane Tech on the South Side, which hosted a concert Monday for all participating student musicians. The other school is Oak Park and River Forest High School, the only non-Chicago school to participate in SEED, which began its pilot year this spring.

At a session last Friday at the high school, OPRF junior Trevor Kazarian said the instruction from professional musicians in a small setting was helpful.

“They’re more detailed, and they concentrate on certain sections of the music,” said Kazarian, 17, who’s played the cello since the age of 5.

Kazarian and four other members of the school orchestra’s string section performed Alexander Borodin’s String Quartet No. 2 in D-minor. Their instructors were specific on having the students listen to each other, one of the most difficult things in playing in small group, said Edward Moore, a professional musician who’s played the cello most of his life and for the last 16 years with Chicago Sinfonietta.

“I absolutely believe it’s necessary for musical development that kids learn how to play in an ensemble,” Moore said. “It’s a different skill than playing with an orchestra, and you have to listen in a different way, and in a way that serves you better.”

Moore and fellow Sinfonietta orchestra member Terrance Gray also instructed the students to sometimes play slow or faster and louder or softer, based, in part, by listening to each other. Working in small groups, particularly in a quartet, the students learn how to blend their playing with others, and how to play in a small ensemble rather than a large orchestra, said Hirsch.

The two musicians have met with students at the school since February, working with them in small groups.

Gray, a violinist with the Sinfonietta, said the most challenging thing for any aspiring musician is not simply listening but learning what to listen for.

“That’s our role,” said Gray, who’s played with the Sinfonietta for all but one of the orchestra’s 20-year existence, “to get them to listen for specific things that will make a piece sound better. If they hear something that they’re suppose to play with or play on top of, or under, you can respond to each other.”