Developing Problem Based Learning Digital Worksheet to Learn Triangle: A Validity Study

Abstract

Students’ understanding of triangle perimeter and area is crucial, as these concepts form a foundational basis for more advanced mathematical learning. However, in practice, the availability of engaging and innovative learning materials remains limited, with teachers typically relying on standard textbooks that often do not fully support conceptual understanding. This study aimed to evaluate the validity of a Problem-Based Learning (PBL)-based digital worksheet designed to enhance learning on triangle perimeter and area. The research applied the 4-D development model (Define, Design, Develop, Disseminate), although only the first three stages were implemented due to time constraints. The participants consisted of four mathematics teachers from the West Bandung area, serving as expert validators. Data were collected using a material expert validation questionnaire with 17 items assessing content accuracy, relevance, and instructional suitability. Descriptive analysis was conducted by calculating the percentage of positive responses for each indicator and interpreting them according to predefined validity criteria. The results showed that alignment with learning objectives scored 83%, material appropriateness 86%, alignment with student characteristics 80%, theoretical suitability 90%, alignment with learning styles 83%, and environmental suitability 93%. The overall validity of the digital worksheet reached 86%, categorized as very valid, indicating its suitability for supporting learning activities and the implementation of the PBL model. In conclusion, the PBL-based digital worksheet demonstrates strong validity and potential to improve students’ understanding of triangle perimeter and area. Further research is recommended to examine its practicality and effectiveness in real classroom settings.