Abstract
The Spiral Progression Approach (SPA), introduced in the Philippine K-12 curriculum, aims to strengthen the continuity and coherence of learning by revisiting concepts at increasing levels of complexity across grade levels. In geometry, vertical articulation is crucial in ensuring that foundational ideas introduced in elementary grades are reinforced and expanded upon in high school, enabling learners to build upon their prior knowledge systematically. Despite its promise, questions remain regarding how effectively this articulation is realized in classroom practice. This study investigated how geometry instruction was articulated vertically across Grades 1 to 10 in the SPA. Specifically, it sought to determine (1) the extent to which the learning content of geometry demonstrates vertical articulation, and (2) the challenges teachers encounter in implementing the approach. A qualitative descriptive-evaluative research design was employed, involving eleven mathematics teachers—five from high school and six from elementary. Data were gathered using a researcher-developed interview questionnaire and analyzed through Provus's Discrepancy Evaluation Model (DEM), guided by Ahmad's (2011) six-step framework for program evaluation. Findings revealed that vertical articulation in geometry is evident in the curriculum but uneven in practice. Effective articulation fostered coherent and interconnected learning experiences that promoted mastery and progression of concepts. However, weak or incomplete articulation resulted in fragmented instruction that limited knowledge transfer across grade levels. Teachers reported persistent challenges such as content overlaps, gaps, and difficulties aligning instructional delivery. The study concludes that strengthening curriculum alignment and providing teacher support are essential for maximizing the effectiveness of the SPA in geometry, ultimately leading to smoother learning progressions and more consistent student outcomes.
