The musical preparation of teachers to work with preschool and school-age children is an essential issue in the global academic discourse. Most studies confirm that many teachers and caregivers of young children have limited knowledge and poor professional skills to organize effective music education. In the world, there is a lack of good musical education for students and in-service training for teachers to meet the expectations of modern curricula It pays attention to different elements of musical preparation, such as knowledge, skills, training, abilities, attitudes, and motivation. This paper presents the model of musical competencies of preschool and school teachers, based on the division of teaching competencies (substantive, methodical, and pedagogical). The authors focus on the musical education and self-esteem of the preschool and school teachers. The article also highlights the need for continuous development of teachers’ musical competence. The supportive strategies to develop the musical competencies and skills of future teachers are crucial.