This study explored the pedagogical beliefs and classroom practices of mathematics teachers and determined whether their beliefs system and practices lean towards the conventional or constructivist pedagogy. It employed the mixed method design and stratified-purposive sampling procedure to identify the 20 participating schools that provided the 96 mathematics teacher-participants. Overall, math teachers held beliefs system and teaching practices that are combinations of both conventional and constructivist perspectives. However, when grouped accordingly, high school math teachers demonstrated classroom practices that leaned more to conventional approaches and are inconsistent with their pedagogical beliefs. Result suggests that math teachers' preparation for K to12 implementation through training seemed not enough to shift their pedagogical perspective to lean more towards constructivism view. Such would likely strain if not impede the effective implementation of K to12 program. Hence, continuous and periodic teacher trainings on how to design a constructivist learning environment are deemed essential.