This photo shows the three winners of the SLSYO concerto competition perched on a balcony overlooking the Powell Symphony Hall stage. Larry Neuman was a high school friend of mine (a year behind me at Clayton). He is a long-time member of the Chicago Symphony [bio]. Leslie Grimm now teaches at Northwestern University in Chicago [ bio]. Jim Stewart appears to also be professional musician, although I could not readily find a bio page.
The SLSYO takes members from ages 12 to 22 (unusual for a youth orchestra). Larry, Leslie, and Jim were all members of the orchestra.