Mathematics is considered to be a human activity and students should actively participate in the learning process. These features are fostered in inquiry-based learning (IBL). IBL is interpreted as a teaching approach that challenges students to solve problem situations before formal explanations and solution procedures are provided. The understanding and practices of IBL might be impacted by teaching cultures, which are considered to be remarkably different in East Asia and the West and have led to stereotypes. This study tried to move beyond these stereotypes and explored the current situations of IBL in lower-secondary mathematics education. China, specifically Beijing, and the Netherlands were taken as examples of the two teaching cultures. Perspectives of students, teachers, textbooks and classroom practices were explored. Chapter 2 focuses on students’ experience of IBL-related activities in mathematics lessons and their preference. 858 Beijing students from 30 classes and 441 Dutch students from 19 classes participated in the survey. Results show that generally the Beijing sample reported experiencing IBL activities in most mathematics lessons and the Dutch sample in some lessons. Students in both samples preferred the same amount of IBL activities as they experienced. Students’ reports show similar patterns. Chapter 3 focuses on beliefs and practices related to IBL described by mathematics teachers. 30 Beijing and 19 Dutch teachers participated in the semi-structured interviews. Results show that the two groups of teachers mentioned many shared IBL beliefs and practices. Compared to the Beijing teachers, although the Dutch teachers did not indicate a more frequent use of IBL as expected, they seemed to describe a lower level of teacher support. Chapter 4 focuses on to what extent opportunities for IBL are provided in mathematics textbooks through analyzing 404 Beijing and 244 Dutch algebra and geometry tasks. Results show many shared IBL features between the Beijing and Dutch textbooks. The textbooks ...