Numerous previous studies have reported the difficulties associated with learning the Brønsted-Lowry acid-base model. The Brønsted-Lowry acid-base model requires complex systems thinking because it considers random interactions between reactant and product particles and effective particle collisions in forward and reverse reactions. The system elements are dynamic, complex, and mutually independent. Furthermore, phenomena constantly change and interconnect with all elements of the system. Despite these difficulties, previous studies, thus far, have not reported methods that can effectively teach students the Brønsted-Lowry acid-base models, which require systems thinking. To solve this problem, we must understand the ontological attributes of science concepts, such as the Brønsted-Lowry acid-base model. In this study, we propose a Scratch program to help students understand the Brønsted-Lowry acid-base model.