What makes a hero heroic? It's not always dramatic acts of bravery. Sometimes, everyday moments of heroism — exhibitions of perseverance, work ethic and courage — speak just as loudly. Close to 100 Durham Academy sixth-graders honored their heroes, from family members to teachers and friends, on Wednesday at an opening reception for their My Hero pop-up books. The literary works of art are on exhibit at downtown Chapel Hill's FRANK Gallery through April 5.