This study addresses the issue of curiosity-driven inquiry learning by examining the interplay among students' inquiry-related curiosity, laboratory engagement, and inquiry abilities and investigates how their learning experiences would associate with such interplay. We employed structural equation modeling to analyze data collected from 920 eighth graders and 1,090 eleventh graders, including their performances on a multimedia-based assessment of scientific inquiry abilities and their responses to items in an online questionnaire. The results revealed that, for students from both grades, inquiry-related curiosity was associated with their inquiry abilities, and that the association was mediated by their inquiry-related laboratory engagement. Furthermore, the analyses showed that both formal and informal experiences were associated with the laboratory engagement of students from both grades through curiosity. Yet, the results indicated that, although the roles of the two types of experiences varied in the associations, formal science experience had stronger associations with students' inquiry abilities than informal science experience for both graders. Taken together, this study supports the importance of having curiosity-driven engagement and suggests that the science education community should collaboratively offer secondary school students such learning opportunities in formal and informal science learning settings.