A 17-year-old girl, India Spellman, and a 14-year-old boy, Von Combs, are charged as adults with murder.
The victim, George Graves, was shot in his driveway near Pickering and East Phil Ellena streets around 3:00 p.m. Wednesday.
He was a Navy veteran and a survivor of World War II. He had been shot once in the chest and was pronounced dead at the scene.
Police say Graves had just finished mowing his lawn when Combs and Spellman approached and tried to rob him.
Graves was shot during the robbery attempt. Investigators say Graves didn't move quickly enough for the teens, and they took that as resistance to their demands.
Police believe Spellman was the person who pulled the trigger.
Police say Combs and Spellman then fled on foot, but were arrested for the crime on Friday.
Combs is from the 1100 block of East Sharpnack Street. Spellman is from the 7900 block of Pickering Street.
In addition to the murder, police are also charging them with another robbery that happened shortly before Graves' killing. Combs and Spellman are also suspects in as many as five other robberies.