The study developed a culturally based standardized scale in Visible Learning for instructional leaders. Descriptive developmental research and qualitative descriptive research were employed in the study. Purposive sampling was used to select expert and target population judges who knew about visible learning, culture, and scale development. The measurement scale development followed the following procedures: Defining the knowledge domain that defined the domains in the most precise terms and then reviewing the literature. This stage searches for knowledge on standardizing scale instruments, gathering conceptual and operational definitions of visible learning and culture. The second stage is item development. This stage covered domain identification, item generation, and content validity. This also covered the specification of response format, and the pooled items were organized per domain. The third stage was scale development, where the different items were organized into measuring constructs. Items on culture were integrated into the different domains of visual learning to describe visual learning in Bicol classrooms. Theoretical or face validation of the developed scale was the fourth stage. This phase utilized expert and population judges to evaluate the items' content relevance and technical quality. The fifth stage was semantic validation, a confirmatory step to gauge the effectiveness of the developed scale when the pilot tested it on respondents. The sixth stage is statistical or empirical validation. The developed scale instrument was administered to the target population to determine its reliability. With Cronbach's alpha of 0.652, the developed culturally based scale possessed internal data consistency. Expert validators, starting from content validity until semantic validation, also established the validity of the scale instrument. Results of the statistical validation revealed that the school where the newly developed scale instrument exemplified visible learning to a great extent.

visible learning, culture, scale, culture-based scale development, standardized scale instrument, instructional leaders, cronbach's alpha