Kim Jones had a routine. A few minutes after 9 each morning, she would step outside her two-story rowhouse on North 12th Street and walk a half-block to Jefferson Street, where the Route 23 bus stopped.

Twenty minutes later, she'd arrive at Turning Points for Children, a Center City agency, where she directed a program that helps the families of kindergartners and first graders in Philadelphia schools.

Her killer knew the routine, too.

At 9:15 Tuesday, as she was waiting for the bus, the 56-year-old mother of two was shot once in the back of the head.

The killer did not take her purse, cellphone, jewelry, or headphones, all of which were undisturbed when police arrived at 12th and Jefferson, just blocks from Temple University's campus. This was not a robbery, Homicide Capt. James Clark said.

"Someone knew that every morning, she got on the bus at that time to go to work, and ambushed her," he said.

Police offered no motive. They asked the public for help in finding a suspect, described as a heavyset black male who was last seen walking west on Jefferson carrying a black duffel bag. Investigators pulled video from SEPTA bus No. 5618, which neared the corner as the crime happened.

A Philadelphia police camera is on the southeast lamppost at the intersection, which is frequented by Temple students, but neighbors questioned whether it was functional. Clark said he was not sure.

Outside Jones' home Tuesday afternoon, neighbors and family members stood in shock. Jones' ex-husband and one of her two adult sons approached the group. "What happened?" the son asked. "What happened?"

A neighbor pointed to the detectives, who stood a half-block up the street.

"She was a churchgoing woman," said Steve Jones, a nephew. "She worked hard. That was about it. For someone to do something like that to her, it's not even computing right now.

"This is unbelievable. This is truly unbelievable."

Jones was due at Turning Points for a 11:45 a.m. meeting with the Department of Human Services, and her coworkers were puzzled by her absence, then stunned at the news.

"We're in the business of helping people," said Mike Vogel, Turning Points' chief executive. "I can't imagine why someone would target somebody like her."

Vogel taught Jones at Rosemont College, then hired her after she completed her M.B.A. Turning Points, which has an office at 15th and Lombard Streets, provides services designed to strengthen families.

For the last seven years, Jones had been program director of the Families and Schools Together (FAST) Program, which works with families at 62 city schools. Its goal is to engage isolated parents.

"There's a curriculum that is designed to help strengthen the family and build stronger relationships between the children and the parents," Vogel said. "There's part of it that helps coach parents to be better parents. It's really about strengthening families and helping parents focus on things as simple as the importance of having dinner together as a family."

Vogel talked softly while two other employees hugged. He said Jones had married in December, just before Christmas.

"She's somebody that was loved and will be missed," Vogel said. "It's hard to wrap your head around."

Wes Hatton, Jones' next-door neighbor since she was a child, described the 1400 block of North 12th Street as quiet, filled with longtime residents. He untied yellow police tape at Jones' property so bus No. 5618, photographed and inspected by crime-scene officials, could return to duty.

"We don't have problems," Hatton said, "with someone trying to catch the bus here."

Anyone with any information on the case is asked to call 215-686-TIPS, police said. There is a $20,000 reward for information leading to arrest and conviction in the case.