Erin Montoya wanted a handful of students at West Marin School, where she teaches Spanish, to know that she recognized their efforts to be leaders among their classmates. She nominated a small group of seventh-graders to represent the school and the West Marin community in Washington, D.C. this summer at the Junior National Young Leaders Conference. To Ms. Montoya’s surprise, she said, five of those students jumped at the opportunity to travel to the nation’s…