The number of English language learners (ELLs) attending schools in the United States is increasing rapidly. In contrast, the number of teacher preservice education programs that specifically train teachers to teach ELLs is increasing more slowly. As a result of this disparity between the number of students and number of trained teachers, school systems must find methods to prepare classroom teachers to provide appropriate and effective instruction for ELLs. A school system in North Carolina has addressed the shortage of trained teachers by mandating professional development in the use of the...