Project-based learning with STEM to promote higher order thinking skills as a strategy to improve high school chemistry learning outcomes

Thinking skills as a cognitive process are life skills needed by students in academic activities. This study aims to implement the Project-Based Learning integrated with Science, Technology, Engineering and Mathematics (PjBL-STEM) to build Higher Order Thinking Skills (HOTS) as a strategy to improve high school chemistry learning outcomes. The study was conducted involving 228 grade 11 high school students that were grouped into experimental and control classes. The research included the development and standardization of the PjBL-STEM model, followed by trials in a school and implementation in several schools. The PjBL-STEM model equipped with innovative learning resources was developed according to the characteristics and learning development of high school students. The implementation of the model includes a pretest, followed by teaching using the developed model versus conventional teaching, and posttests. The PjBL-STEM model effectively facilitates students’ active learning in completing project assignments. The HOTS score achieved from subjective assessment of project products from model implementation (M = 84.03 ± 4.68) is relatively high. Student learning outcomes in the experimental group (M = 84.92 ± 4.95) were higher than those in the control group (M = 70.36 ± 5.62). The average normalized gain in the experimental class (NG = 0.81) is very large, confirming that the PjBL-STEM model is very effective in improving chemistry learning outcomes. Correlation analysis proves that HOTS achievement is positively correlated with increasing chemistry learning outcomes (r = 0.91–0.94). The PjBL-STEM model is relatively new to SHS chemistry teaching and is suitable to facilitate students learning holistically in achieving learning outcomes.