Natural science itself is an experimental science, so practice and experimentation are important and are typical teaching methods of this subject. To make practice and experiment play the highest strengths in teaching and developing the ability to learn about nature - one of the three specific competencies of natural science, the association of experiments with scientific methods plays a special role. This article presents the general problems of teaching practical experiments according to the scientific method and applying it in teaching the topic "Living animals" in Natural Science, grade 7. The research results can be teachers' references in teaching Natural Science to meet the teaching objectives in the direction of developing students' capacity in Vietnam in the current period.