The research aims to analyze and determine the essence and forms of organization of professional competence of natural science teachers as an essential aspect in the formation of fundamental knowledge and scientific literacy of students. This structural characteristic determines a teacher’s abilities, depending on the acquired knowledge and professional experience, directed to solving typical professional difficulties that arise in several situations during teaching activities. This research examines the essence and forms of organization of competencies of natural science teachers in teaching biology and chemistry at school. During the research, the authors carried out the analysis of variance (ANOVA) and calculations of paired Student’s t-tests to determine indicators of creative psychological and pedagogical technology elements used by teachers in teaching chemistry before and after pedagogical experiments. The statistical values obtained from the variance analysis showed significant differences, absolute changes, and growth rates between science teachers who were able to practice elements of creative psychological teaching and critical thinking in teaching chemistry. Professionally, competent teachers form students’ creative abilities in the education process and achieve positive results in professional activity.