Evaluating the Effect of Predict-Observe-Explain Activities on Students' Critical Thinking in Acid-Base Reactions at Sokoto Technical Schools

Critical thinking distinguishes students who genuinely understand chemistry from those who merely memorize facts, yet most instructional approaches fail to cultivate analytical skills in technical education contexts. Here we address the missing evidence on whether structured prediction-observation sequences can systematically build critical thinking capacities in acid-base chemistry. In a quasi-experimental study with 147 Nigerian technical college students, we demonstrate that Predict-Observe-Explain activities produce significantly larger gains in critical thinking compared to conventional instruction. Students in the POE group improved from 11.57 (SD = 3.31) to 20.92 (SD = 3.69) on a 75-point assessment, while controls improved from 11.73 (SD = 3.24) to only 15.82 (SD = 3.18). The group difference at posttest was statistically significant (p < .001) with a large effect size (Cohen's d = 1.24). Low achievers derived the greatest benefit, gaining 5.67 points more than their control group counterparts. Quality of POE engagement strongly predicted practical problem-solving performance (partial r = .59, p < .001) after controlling for prior ability. These findings establish that critical thinking can be systematically taught through cognitive conflict generated by prediction-observation discrepancies. For technical schools preparing students for laboratory careers, this work provides an accessible, resource-appropriate strategy for developing the analytical competence that industry demands.