The effectiveness of the integrated GASING method combining contextual teaching and learning on elementary school students’ mathematical communication skills: a quasi-experimental study

Source abstract

This study evaluated the effectiveness of the GASING method combined with the Contextual Teaching and Learning (CTL) approach on elementary students' mathematical communication skills relative to conventional instruction. A quasi-experimental pretest-posttest design with nonequivalent groups was used, involving 128 fourth-grade students: an experimental group (n = 55; SD Kristen Baik classes 4A-4B and SD Inpres Kemiri) taught with GASING-CTL, and a control group (n = 73; SD Inpres Kartika classes 4A-4B and SD YPPGI Sentani) receiving conventional instruction. Pretest scores did not differ significantly between groups (p = .891), confirming baseline equivalence. Both groups improved significantly from pretest to posttest (experimental: t = -20.19, p < .001, d = 2.72; control: t = -16.47, p < .001, d = 1.93), with higher posttest means in the experimental group (M = 73.59, SD = 8.85) than the control group (M = 67.39, SD = 8.99). Because the control group's normalized gain (N-Gain) departed from normality (Shapiro-Wilk p < .001), a Mann-Whitney U test was applied and showed a significant between-group difference favoring the experimental group (U = 2582.00, Z = 2.77, p = .006, r = .244), although the independent t-test on raw gain scores was not significant (t = 1.55, p = .123). Mean N-Gain fell in the "medium" category for both groups (.63 and .53, respectively), yet the experimental group showed a larger share of "high" gains (32.7% vs. 16.4%) and no "low" gains, versus 11.0% in the control group. These results suggest GASING-CTL yields more consistent and proportionally larger learning gains, supporting its potential as a contextual strategy for enhancing mathematical communication skills, though the non-significant raw gain difference warrants cautious interpretation.