When Kimberly Bleier or one of her three children wake up not feeling well, Bleier is “instantly in panic mode,” thinking not about their health, but about her students at Concord High School. 

Bleier, who teaches social studies to grades 9 through 12, knows that if she can’t go to school, one of three things will happen. Ideally, a substitute teacher will be called in for the day. But that’s uncertain due to an ongoing substitute teacher shortage. More likely, colleagues will forgo their prep periods to cover her classes. Rarely, if lots of teachers are out, there’s what Bleier calls a “warehouse situation,” where one adult oversees multiple classrooms of students in the cafeteria or another area of the school.