This study aimed to determine whether the Illuminative Evaluation Model, with its three-stage framework: Investigate, Inquire further, and Explain, can be used as a methodology in understanding the influences of the hidden curriculum on the character development of preschool students. In Stage 1: Investigate, document analysis, observations, and interviews were conducted to examine the characteristics aimed to be developed through the formal curriculum, and the deviations and unintended outcomes that occurred during implementation. In Stage 2: Inquire further, surveys, structured observations, and focus-group discussions were conducted to progressively focus on selected issues. In Stage 3: Explain, principles and patterns were organized to describe the hidden curriculum.

Findings revealed that the hidden curriculum functioned through the following: (1) inculcation of school values and principles; (2) use of various approaches to character development; (3) development of readiness for formal schooling; (4) functions of the physical environment; and (5) consideration of managerial and policy concerns beyond classroom doors. In conclusion, the Illuminative Evaluation Model was found to be effective as a tool in determining the influences of hidden curriculum on students’ character development. Based on this study, it is recommended that in order to serve the purposes of illumination with respect to the hidden curriculum, the model’s questions for Stage 1 should include inquiries not only on the disparities between the instructional system and the learning milieu but also on the features of the school program which leads to congruency in the achievement of goals. Furthermore, in order to strengthen the feasibility of using the Illuminative Evaluation Model in the study of the hidden curriculum, other aspects of student development can also be taken into account.