This paper describes an evaluation to verify the reliability, sensitivity, and effectiveness of the checklist. An improvement of the checklist is also described. The checklist, based on flow theory, was developed as a support tool for teachers and courseware designers to redesign learning materials and environments from the view point of motivational design. After the literature review of the applied research on flow theory to the educational field, it is found that there are few practical tools proposed. This paper focuses on the formative evaluation of the flow-theory-based checklist, which has been already proposed, and the verification of its reliability, sensitivity, and effectiveness. To carry out the whole evaluation experiment, the e-learning materials were developed and the preliminary experiment, the expert review, and the evaluation experiment were performed. As a result, the checklist is found to be practical enough and the future tasks are clarified.