CONYERS, Ga. (AP) -- In the wake of the nation's latest school shooting, administrators insisted they had done everything possible to avoid such an incident. ``Over the course of the day, I've talked with at least 20 different experts about whether we could have done anything differently -- and the answer was emphatically no,'' said Jim Borland, a Rockdale County Board of Education member. ``Nothing can prevent what happened.'' A 15-year-old sophomore armed with two guns opened fire Thursday morning at Heritage High School in Conyers, shooting six classmates. None of the injuries was critical. Hours after the shooting, about 100 parents attended a regularly scheduled school board meeting. Only one parent commented, volunteering to patrol the halls if it would help make the school a safer place. ``What do we need to do more to protect our kids?'' asked Jody Isom, whose 15-year-old daughter, Lindsay, attends Heritage. ``The main thing is that we need more interaction with the kids, and if that means volunteering, I'll be the first one to do it.'' School Superintendent Donald Peccia and Borland said security is a priority. Both have opposed installing metal detectors, though Heritage has video surveillance cameras and an armed sheriff's deputy. Sheriff Jim Wigington said today that the deputy's day begins at 8:30 a.m., so he was not on duty at the time of Thursday's 8 a.m. shooting. He arrived shortly afterward, however, and helped direct the students as they evacuated the school, Wigington said. Heritage students said that after the April 20 school massacre at Columbine High School in Littleton, Colo., teachers went over the school's crisis plan but did not hold lockdown drills. Peccia also sent home a letter with students saying that any copycat incidents would not be tolerated. ``As soon as we are aware of any rumors, threats or allegations, my staff and I will take prompt action to investigate the situation completely and call the police for assistance,'' said the letter, dated April 29. ``Strict disciplinary consequences will be assigned to any student and to anyone else exhibiting such behavior.'' Peccia said a deputy will be posted at every Rockdale school until the end of the school year. Classes continued today at all schools except Heritage, and Peccia said attendance was about normal. Classes at Heritage are set to resume Monday, and graduation there is scheduled for a week from today. ``We cannot let something like this slow us down,'' Peccia said. ``And we will not tolerate anyone trying to take it away from us.'' Debby Stephens, whose daughter attends Heritage, said she has no qualms about sending her child back to school. ``But the truth is that unless we do something to change the minds of these kids, it's going to happen again,'' she said. -=-=- 