The location of a school is one of the factors that influence the distribution of staff with different levels of experience and qualifications. In the United States, for example, urban school districts serving disadvantaged populations face particular teacher shortages, although there is great variation between districts (Papay et al., This often results in abelow-average share of experienced and highly-trained teachers (Monk, 2007(m], Gagnon and Mattingly, 2012[n4]), and curriculum areas being covered by one teacher and teachers with little subject-specific training.