A teenager pleaded guilty Thursday to all 55 counts, including murder, in the mass shooting at Apalachee High School in Georgia nearly two years ago that left two students and two teachers dead. The plea closes a chapter in a case that reignited national grief over gun violence in American schools, a tragedy that once again forced a community to bury children and educators lost to gunfire in a place meant to be safe. The shooting became another entry in a grim and recurring pattern that has left parents, teachers, and lawmakers grappling with how such violence keeps happening despite repeated warnings and prior incidents involving young shooters. For the families of the victims, the guilty plea offers a measure of legal resolution, though it does little to quiet the broader questions the case raised about access to firearms, warning signs among troubled teens, and the responsibility of schools and communities to prevent the next tragedy before it occurs. The case is expected to renew calls for stronger action to protect students nationwide.