<![CDATA[This research was conducted because of the encouragement in the implementation of Pancasila Education learning in Elementary Schools which is often conceptual and abstract and the integration of local culture is still limited, resulting in low critical thinking skills of students. The purpose of this study is to develop valid, practical, and effective digital teaching materials in the form of NOBULA e-books (Local Cultural Norms) to improve the critical thinking skills of fifth grade students of SDN Ngadiluwih I. This study uses the Research and Development (R&D) method with the ADDIE model which includes Analysis, Design, Development, Implementation, Evaluation. The research subjects were 53 fifth grade students divided into 27 experimental class students and 26 control class students. Data collection instruments included validation sheets, user questionnaires, and critical thinking test questions. The results of the validity test by material experts were 82%, teaching materials 90%, and test questions 89%, all validity test results included the very valid category. The practicality test by user responses, students was 82% and teachers 98% which showed very practical criteria. Furthermore, the t-test showed a significant difference between the two classes (0.029 < 0.050). The N-Gain value of 59.21% for the experimental class and 49.94% for the control class proved that the experimental class was quite effective. The effect size calculation of 0.61 is considered quite effective. Thus, it can be concluded that the NOBULA e-book improves critical thinking skills in elementary school students]]>
