I found this on John Chuckman's Chicago Nostalgia and Memorabilia site. Roosevelt High School had an AT-6 after the war for the Aero Shop class:

The only yearbook photo I could find was from the class of 1948; note it still had its wings:

All I can see of the serial is 41-159?? - the L244 code means it came from Minter Field. Anyone know more? The school also had a Link Trainer.