Katie O’Neil, one of the hundreds of Marietta High seniors who will graduate on Saturday at Northcutt Stadium, is “a really fantastic person,” according to one of her instructors. “She enjoys learning, takes smart risks and consistently strives for her personal best,” said Debra R. Woolard, who coordinates the school’s rigorous International Baccalaureate program, which drew Katie to the school. But school is not all about the books ...