Since fifth grade, Thomas Hughes has anticipated the litany of rituals that define senior year at St. Margaret’s Episcopal School in San Juan Capistrano, California.There’s Senior Sunrise, when kids arrive at dawn to watch the sun come up. There’s Senior Banquet, when juniors serve seniors a fancy meal, and the 50-days-until-graduation lunch. Then there’s the awards ceremony, the water balloon fight, prom, graduation and a