Pengaruh Blooket (Tower Defense) terhadap Kosakata Bahasa Jerman Siswa SMA: Analisis Eksperimen Semu dengan Kontrol Kovariat

Abstract

Research into the use of game-based interactive media has generally not evaluated its effectiveness in depth through group comparisons that account for baseline disparities, particularly in the teaching of German vocabulary, which is often characterised by low motivation and repetitive teaching methods. This study addresses this gap by examining the effect of the Blooket platform, an interactive, gamified quiz-based digital learning tool, specifically its ‘Tower Defense’ mode, on senior high school students’ German vocabulary learning outcomes across experimental and control groups. Data collection was carried out through pre- and post-tests involving 47 eleventh-grade students at SMAN 19 Bandung and analysed using descriptive statistics, nonparametric tests, and Analysis of Covariance (ANCOVA). The results indicate that both groups experienced a significant improvement in learning outcomes following the intervention. At the raw-score level, the group using the Blooket platform showed higher relative gains compared to the control group: the N-Gain of the experimental group reached 0.79 (high category) versus 0.48 (moderate category) for the control group, with a within-group effect size (Cohen's d) of 1.43 compared to 0.83 in the control group. However, because the pretest scores between groups were not equivalent at baseline (85.74 vs. 73.50), statistical control using ANCOVA was conducted, revealing that the difference in adjusted posttest means between the two groups was not statistically significant (). These findings suggest that the Tower Defense mode is associated with short-term improvement in German vocabulary scores, but its superiority over conventional instruction is not empirically supported, particularly for learners with high baseline ability, for whom a ceiling effect limits measurable gains.