Some of the musicians were part of a fundraiser for Ukraine earlier this year.
St. Nicholas has 70 new students whose families fled the fighting in Ukraine. Olena Raczkiewycz has two children at the school.
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"It's important because we feel, like, in community," Raczkiewycz said.
Also as part of Friday's concert, the school choir sang and all joined together for the Ukrainian national anthem.
"Just amazing. The strength in their voices, just incredibly powerful," said Lyric Opera of Chicago Orchestra Principal Bassoonist Preman Tilson.
Hearing the anthem was bittersweet for some, like 12-year-old Nazar, who left his father and grandparents in Ukraine.
"Maybe a little hard. Like, we are here. We can eat. We can sleep. We can do whatever we want, but in Ukraine, you can't do all these things," Nazar said.
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The school offers a Ukrainian class, a place where children can speak and sing in their native languages.
"When you hear and sing your own song it makes you so happy and feel so good so the music is the medicine for all of those hard feelings for Ukrainian children," said Irene Dychiy, a St. Nicholas foreign language teacher.
The new families to St. Nicholas are not sure what their futures holds, but for now, they are safe and can find familiarity and fellowship.