About 700 teachers on the Department of Education payroll have no permanent assignment but instead work as substitutes, and they’ve cost the city $81 million, according to the New Teacher Project. But apparently none was available to help out at Manhattan’s P.S. 163 recently when a second-grade teacher was out for four days because of a family emergency. Parents say instead of assigning a sub, the school reassigned kids to other classrooms (some in first grade, some in second, some in third) and, worse, never told them about it. When parents questioned the move, which apparently unsettled some of the kids, “we got a bunch of different answers,” says mom Nancy Eichenbaum. “They said they couldn’t get a sub because it was the end of the year [and that] they didn’t have a budget for subs.” According to the DOE, teachers in the Absent Teacher Reserve are assigned to specific, larger schools with frequent need for temps; other subs cost $160 per day. P.S. 163’s principal declined to comment.