In Livingston, Calif., elementary school principal Mayte Ramirez stands at her desk looking over a list of students who were absent today. It's a Monday, and it's longer than usual. RAMIREZ: Out of town, out of town, sick, tardy, sick per mom, sick per mom. TURNER: Ramirez then looks to see who among these kids is now chronically absent. That means they've missed 10% of the school year. She picks a kindergartener.