There’s the 14-year-old who has been playing violin since he was 4 and says his school orchestra isn’t challenging enough; the homeschooled boy, also a violinist, who takes private lessons, but wants to learn to play with other musicians; and the cellist from Scituate whose high school doesn’t have a program for strings.

They are a few of the 15 or so teen musicians whose backpacks and instrument cases are strewn across Marshfield High School’s band room as they sit, violins and cellos in hand, playing Beethoven’s Coriolan Overture. These are some of the string players in Bay Youth Symphony, the South Shore Conservatory’s three-leveled youth orchestra.