Ndungo, IssaBalimuttajjo, SudiAkugizibwe, Edwin2025-04-252025-04-252025-04-11Ndungo, I., Balimuttajjo, S. & Akugizibwe, E. (2025). Transformation Geometry Attitude Scale (TGAS): Development and Validation for Secondary School Learners in Uganda. International Journal of Advanced Research, 8(1), 140-150. https://doi.org/10.37284/ijar.8.1.28612707-78102707-7802https://doi.org/10.37284/ijar.8.1.2861https://nru.uncst.go.ug/handle/123456789/11224Transformation geometry, a core topic in secondary school mathematics, strengthens students' spatial reasoning and problem-solving skills. Students’ attitudes toward transformation geometry significantly influence their engagement, motivation, and achievement in mathematics. However, existing attitude scales either focus on general mathematics/geometry, are designed for other educational levels or were developed outside Uganda, limiting their contextual relevance. This study aimed to develop and validate the Transformation Geometry Attitude Scale (TGAS) for assessing Ugandan secondary school learners' attitudes. The scale was developed through expert consultations and piloted among 132 secondary students. Validation involved Exploratory Factor Analysis (EFA) and reliability testing. The initial 36-item scale (α = 0.85) was refined to 22 items across three dimensions: Interest &amp; Confidence (α = 0.80), Engagement &amp; Metacognition (α = 0.77), and Relevance &amp; Applications (α = 0.85). The validated TGAS provides a reliable tool for evaluating students’ attitudes and informing instructional strategies in transformation geometry. Future research should apply Confirmatory Factor Analysis (CFA) across diverse educational settings to further validate its structure</jats:p>enjournal-article10.37284/ijar.8.1.2861