The ranks of non-teachers—such as administrators, counselors, teacher aides and cafeteria workers—has swelled 130 percent since 1970 and they now make up 50 percent of all public school employees according to a new study, The Hidden Half: School Employees Who Don’t Teach.Looking at data from the National Center for Education Statistics (NCES), the Thomas B. Fordham Institute found that the growth of non-teaching staff has greatly outpaced student growth over the past four decades.From 1970 to 2010, the number of students grew by 8.6 percent, while the number of non-teaching personnel increased by 130 percent. Non-teachers now consume over a...