Developing Van Hiele-Based Project Learning Tools through Plastic Waste Paving Block Design on Similarity Materials
This study aimed to develop Project Based Learning (PjBL) instructional tools through plastic-waste paving block design based on Van Hiele theory that are valid and practical for learning similarity topics. The study employed a Research and Development (R&D) approach using the 4D model developed by Thiagarajan, consisting of the define, design, develop, and disseminate stages. The participants were seventh-grade students of SMP Science Quran Al Irsyad Al Islamiyyah Jember in the 2025/2026 academic year, consisting of an experimental class and a control class. Data were collected using validation sheets, observation sheets, student response questionnaires, and readability instruments. The results indicated that the developed instructional tools met the validity criteria, with validity scores of 3.76 for the teaching module, 3.67 for the student worksheet, and 3.72 for the user guide. The practicality criteria were also achieved, as indicated by a learning implementation score of 3.5 (high category), student activity of 90% (very good category), and student responses of 92% (very positive category). These findings indicate that Project Based Learning instructional tools integrating Van Hiele theory and plastic waste paving block design are valid and practical for supporting geometry learning on similarity topics through authentic project activities involving plastic-waste paving block design.