Given the increasing needs of employees with computational skills, understanding the core competencies of K-12 computer science (CS) education is vital. This phenomenological research aims to identify critical factors of CS education in K-12 schools from the perspectives and visions of CS faculties in higher education and teachers in K-12 schools. This study adopted a phenomenological research design. The researchers conducted a semi-structured interview with 13 CS faculties and K-12 CS teachers in Michigan and analyzed the data using thematic analysis. The findings indicated that: (1) the core competencies for K-12 CS education include problem-solving through computational thinking, math background, and foundational programming skills, and (2) what is essential is not the programming languages taught in K-12 schools but computational thinking, which enables the learners to easily transfer from one language environment to another. The findings provide important implications for K-12 CS education regarding the core competencies and programming languages to be taught.