The strategies employed by teachers and students in the open inquiry-based learning approach are crucial, especially when presenting researchable questions formulated by students under the guidance of the teacher. This effectively promotes the teaching and learning of various disciplines. Participant observation was conducted in the science classroom for secondary education teachers to establish the level achieved by teachers in the development of the open inquiry-based learning experience and to identify the taxonomic level of researchable questions (RQs). An observation rubric was applied, revealing that 83% of in-service teachers reached a satisfactory level, while 67% of pre-service teachers were classified as unsatisfactory in terms of using the open inquiry-based approach. Both groups formulated high-order inquiry questions, with a clear inclination in favor of in-service teachers compared to pre-service teachers. These results highlight the importance of university training in focusing on inquiry skills, particularly in planning, inferences, and evaluation. Through this observational analysis, valuable information about the current state of open inquiry-based learning is contributed, advancing science education in Peru.