Notes: Data are for teachers in public noncharter schools. According to research and to the U.S. Department of Education, highly qualified teachers have the following four credentials: They are fully certified (with a regular, standard state certificate or advanced professional certificate versus not having completed all the steps); they took a traditional route into teaching (participated in a traditional certification program versus an alternative certification program, the latter of which is defined in the teacher survey questionnaire as “a program that was designed to expedite the transition of nonteachers to a teaching career, for example, a state, district, or university alternative certification program”); they are experienced (have more than 5 years of experience); and they have a background in the subject of main assignment, i.e., they have a bachelor's or master's degree in the main teaching assignment field (general education, special education, or subject-matter specific degree) versus having no educational background in the subject of main assignment.