Impact of The STEM approach with formative assessment in PjBL on students' critical thinking skills

Abstract

Critical thinking skills (CTS) are skills that need to be developed in the 21st century. However, building students' CTS through a STEM approach with formative assessment in project-based learning (PjBL-STEM-AF) is rarely done. This study aims to investigate the impact of STEM-AF in PjBL in constructing students' CTS in the topic of fluid statics. This study used a quasy experiment with a pretest-posttest control group design with students of class XI in Malang, Indonesia, as subjects. PjBL-STEM-AF model and the PjBL model was applied to the Experimental and Comparison classes, respectively. Students made two projects, namely a pressure element HARTL and a simple boat project. The research instrument was 9 essay items of critical thinking skills test with a reliability of 0.625. The data were analyzed by t-test, N-gain, and d-effect size. The results showed that the CTS in the Experimental class with a mean of 65.19 and an increase of 0.52 (medium) was significantly higher than the comparison class with 52.36 and 0.35 (medium). Experimental class' students have different levels of improvement on the likelihood and uncertainty analysis indicator. However, the two classes had almost the same increase in the indicator of problem-solving and decision-making, and an increase in the low category on the hypothesis testing indicator. The value of effect size at 1.13 (Very Large category) suggests that PjBL-STEM-AF learning should be done more frequently in the field. The Experimental class students gave a more positive learning response than the Comparison class. It is recommended in future studies to add an "Art"aspect to the STEM approach to develop students' CTS further.