Purpose: The purpose of this study is to develop a novel guided inquiry-based pedagogical practice embedded into regular library and information science (LIS) courses to improve LIS students' information literacy (IL) in a developing country. Design/methodology/approach: A guided inquiry-based pedagogical practice for IL instruction was introduced and embedded into two regular courses in an LIS school. The effectiveness of the new approach was evaluated in a longitudinal pre-test- and post-test-based teaching intervention with a control group. Findings: All aspects of IL skills improved among the students participating in the teaching intervention showcasing the benefits of the inquiry-based pedagogical practice. In addition, the students in the intervention group learned the course subject content more in depth than students in the control group. However, no consistent learning benefits were achieved in IL knowledge, and only sporadic associations were found between IL knowledge and skills. Originality/value: This study breaks new ground in IL teaching intervention in LIS schools. To the best of the authors' knowledge, it is the first to apply an inquiry-based approach, embed teaching into more than one regular course, collect pre-test and post-test data to evaluate learning outcomes in IL knowledge and skills and control learning outcomes in subject contents.