In e-learning, the flip blended learning model is used to provide students with learning contents inside/outside classrooms. It encourages students to preview these contents outside classrooms before the lesson. Then, various learning activities are taken inside classrooms in the lesson. An important issue about its success is the effectiveness of the preview because it affects the subsequent learning activities in the lesson. Further, for an ePUB3 ebook-based learning model, ePUB3 ebooks are used and hence embedded ePUB3 track and test functions can be used for tracking the preview accesses on these eBooks and examining the preview outcomes. As such, the preview effectiveness can be captured by checking these accesses and their relationships with the test outcomes for making adequate actions on subsequent lesson activities. In this paper, the authors explore such an effectiveness study on the preview of learning contents via ePUB3 track and test functions. For illustration, this study is applied to a script writing course and respective discussions are presented for showing its usefulness.