Civic engagement for climate protection initiates collective processes to pursue structural changes towards the mitigation of climate change. To our best knowledge, no validated scale on civic engagement for climate protection of school students exists. This study aims to examine the psychometric characteristics of a new measure. Baseline data from the Public Climate School study 2023 was used to assess item properties and factor structure of an 8-item scale. A total of N = 360 school students (Mage = 14 years, SD = 1.19, 49% female) from seven schools in Germany completed the measurement. Correlational analyses were conducted with theory-derived measures, including individual consumption behaviors to reduce one’s ecological footprint, enactment of social influence, perceived knowledge about engagement options, risk perception, self- and collective efficacy beliefs, ingroup identification, and ingroup norms. All items of the civic engagement scale had right-skewed distributions. Exploratory factor analysis indicated one-dimensionality of the construct. The scale showed good reliability (McDonald’s ω = .86) and differed from other climate protection behaviors. Associations of civic engagement with related variables were consistent with theoretical assumptions. Results indicate applicability of the scale to measure propensity for civic engagement for climate protection, warranting replication in school contexts of other countries.