CHARLESTON, S.C. (WCSC) —While summer is in full swing, the Lowcountry’s school districts are working to make sure their teacher vacancy numbers get down to zero so no child gets left behind on the first day of school. The Center for Educator Recruitment, Retention and Advancement, one of the oldest retention groups in the country, said teacher vacancies went down by 32% at the start of last year compared to the year before across the state.