<![CDATA[Science process skills (SPS) are essential competencies for preservice primary school teachers because they support scientific inquiry and inquiry-oriented science instruction. However, previous studies indicate limited empirical evidence regarding the use of authentic local environmental phenomena as a field-based inquiry context for developing SPS among prospective teachers. This study aimed to examine how science learning grounded in local phenomena supports SPS development among preservice primary school teachers. A quantitative quasi-experimental design with a pretest–posttest control group structure was employed with 67 participants: an experimental group (n = 34) and a control group (n = 33). The intervention was conducted over six weeks through inquiry activities based on local environmental phenomena in Magetan, East Java, Indonesia. Data were analyzed using descriptive statistics, normalized gain (N-gain), and Analysis of Covariance (ANCOVA). The results showed that the experimental group achieved higher posttest SPS scores (M = 82.47) than the control group (M = 69.32), with greater improvement reflected in N-gain values (0.60 and 0.30, respectively). ANCOVA revealed a significant treatment effect after controlling for pretest differences, F(1,63) = 30.24, p < .001, partial η² = .321. The largest gains occurred in designing investigations, interpreting data, and predicting. These findings suggest that locally phenomena-based science learning was effective in supporting SPS development within the context of this study. The study contributes to the science education literature by providing empirical evidence on integrating authentic local environmental phenomena into field-based inquiry learning to strengthen SPS among preservice primary school teachers.]]>
