Implementation of Problem-Based Learning Assisted by Flashcards to Improve Students' Critical Thinking Skills on Landscape Material

This study examines the implementation of Problem-Based Learning (PBL) assisted by flashcard media to improve third-grade elementary students’ critical thinking skills in Landscape (Bentang Alam) material. Methods: This study used a quantitative approach with a quasi-experimental, nonequivalent control-group design. The sample consisted of 44 third-grade students from SD Negeri in Semarang, divided into an experimental class (22 students) taught using PBL assisted by flashcards and a control class (22 students) taught using conventional learning. Data were collected using pretest and posttest instruments with 120 multiple-choice items (30 per skill) and analyzed using normality and homogeneity tests, paired-sample t-tests, independent-sample t-tests, Normalized Gain (N-Gain) analysis, and analysis of Covariance (ANCOVA) with the pretest as the covariate. Because of third-grade students' cognitive capacity, the test was administered in four separate sessions on four different days, with each session lasting approximately 45 minutes. Effect size was reported using Partial Eta Squared to measure the magnitude of the intervention’s impact. Both groups showed increased critical thinking ability after treatment, but the experimental group's increase was significantly higher than the control group's. After controlling for pretest scores, the ANCOVA results showed a significant difference between groups (F = 16989.679; p < .001; η²p = .998), indicating a large effect size. The experimental group's average N-Gain score was 0.7336, categorized as high and fairly effective, while the control group's average was 0.3784, categorized as medium and less effective. The greatest improvement occurred in the analysis and evaluation indicators. Implementing PBL assisted by flashcards effectively improves students’ critical thinking skills on Landscape material, as flashcards function not merely as visual media but as contextual problem triggers integrated into each stage of the PBL syntax.