Objective: This research focused on identifying and classifying the scientific skills present in Chilean school textbooks of Natural Sciences from the first to the fourth year of Basic Education. Theoretical Framework: We sought to determine their presence, frequency, cognitive level and types of skills, comparing them with curricular documents and UNESCO declarations on the subject. Method: The study, descriptive in nature, employed the integrative method, using document analysis to compile quotations, patterns of behavior and categories. For quantitative aspects, descriptive statistics were used, analyzing by course and thematic units. Results and Discussion: It was found that the most promoted skills were observation and explanation, fundamental for scientific learning. Scientific skills were identified at all educational levels, varying in frequency. Third and fourth year showed a greater frequency and variety of higher cognitive level skills, although some, such as creating, evaluating, reflecting and imagining, did not have the expected frequency. The lower cognitive skills did not show significant differences between educational levels. The scientific skills present in the school texts coincide in general with those declared in the Curricular Bases and by UNESCO, both in type and educational level. Implications of the investigation: the investigation implies that the scientific skills that declare the Curriculum Bases and scientific literature are promoted, mostly, in school texts on Natural Sciences for basic education, verifying correspondence between the documents. Originality/Value: the study contributes to literature by contributing new knowledge to the state of affairs of the knowledge of Natural Sciences in basic education, as well as highlighting the need to promote more creativity and imagination in school texts. At the same time, the results will be an input for teachers to pay more attention to higher-level scientific processes.