This literature review synthesized current research on preservice and in-service programs that improve K–6 teachers’ attitudes, self-efficacy, or knowledge to teach computing, coding, or computational thinking. A review of current computing training for elementary teachers revealed 21 studies: 12 involving preservice teachers and nine involving in-service teachers. The findings suggest that training that includes active participation can improve teachers’ computing self-efficacy, attitudes, and knowledge. Because most of these studies were fairly short-term and content-focused, research is especially needed about long-term outcomes; pedagogical knowledge and beliefs; and relationships among teacher training, contexts, and outcomes.