Attendance Works and the Campaign for Grade-Level Reading, February 2014. This brief summarizes a growing body of research which documents how many youngsters are chronically absent, meaning they miss 10 percent or more of the school year due to excused or unexcused absences. The research also shows how these missed days, as early as preschool, translate into weaker reading skills and makes a clear case for engaging families to reduce chronic absenteeism.