Overseeing educational transformation demands a rethink of pedagogical practice according to a more in-depth understanding of learning and assessment as a single formative process. The aim of the present article is to describe the elaboration and validation an instrument that seeks to investigate student perceptions of the culture of assessment as learning. The study is exploratory and descriptive in nature and comprises 505 primary and secondary school students from the region of La Araucanía, Chile. Content validity of the instrument was examined by an expert panel. Further, reliability was determined according to Cronbach’s Alpha coefficient and MacDonald’s Omega indicator, whilst construct analysis included the development of exploratory and confirmatory factor analysis and structural equation models. Findings revealed a scale made up of three factors: culture of self-assessment, culture of collaboration and technological culture of learning. The instrument meets requisites for statistical rigour required for its application in the school system. It can be concluded that this instrument contributes to the discussion on the integration of assessment and learning as a single construct. The instrument also contributes redefining assessment practices by providing a reference that encourages self-assessment and reflection on the profound learning opportunities that are provided by schools in the 21st century