Two case studies were conducted to examine whether inquiry-based learning (IBL) can help students in understanding normal distributions, and to determine if IBL methods have any effect on students' conceptual and computational capabilities. There were 16 students in the traditional class and 17 students in the IBL-implemented class who participated in each of two case studies. The experimental group performed significantly better than the control group in terms of conceptual understanding and computational skills. These outcomes suggest that IBL methods such as discussions, asking questions, and guided lectures helped students to develop statistical reasoning.