There is no standardized definition or measurement tool for sustainability competence, which hinders comparative research. This study addresses this gap by developing a new test based on the European reference framework GreenComp. The proposed instrument, consisting of eleven multiple-choice items, was validated through expert review and exploratory and confirmatory factor analysis, showing strong construct validity and high internal consistency reliability. Applied to students aged 8 to 12, it revealed a prevalence of basic and anthropocentric perspectives on sustainability. This promising tool can assess sustainability competence in primary education and has the potential for use across European countries.
