A high level of interpretive skills is crucial for the functioning of society as a whole. Today, when people are increasingly exposed to various sources of information of varying quality and we live in a so-called post-truth world, the ability to critically evaluate and correctly interpret data is essential for informed decision-making in society. Scientific literacy, supported by the ability to formulate valid and meaningful conclusions, becomes a prerequisite for solving complex problems in science, technology, and everyday life. One approach used to develop these skills in students of various age groups is inquiry-based learning. The aim of this study was to find out how students’ interpretive skills focusing on the conclusion of research are developed by solving inquiry-based tasks. To this purpose, forty-five lower-secondary students solved six inquiry-based tasks focusing on biological topics: molluscs, yeast, flowers, heartbeat, papillary patterns, and osmotic phenomena in cells. Students solved the tasks and wrote down their solutions. Students were given feedback on their solutions. Students’ solutions were analysed using closed coding and qualitatively described. Positive trends in the formulation of the conclusion were found. While in the first task only 84% of the students related the conclusion to the problem solved, in the case of the last task all students did. An improvement trend was also found in supporting conclusions with specific findings. This method of teaching biology seems to be effective in supporting the development of interpretive scientific skills and thus may be a suitable way to develop students' scientific literacy.

Keywords: Scientific skills, STEM, science education, secondary education.