本研究初探兩位有經驗的國小數學教師對於素養導向教學的認識與課堂實踐，參與教師加入由研究者所組成之教師專業學習社群，和不同教育階段的教師在團隊中撰寫數學素養導向教材。在社群運作兩年多之後，研究者以半結構訪談方式，輔以分析她們所撰寫完成的教材，探討其對於數學核心素養的理解。研究發現，參與教師對於核心素養的理解涵蓋三面九項的其中五項；教師進行素養導向教學時，以學生為中心，善用師生對話來探索學生的想法，邀請學生參與課室討論，以及要求學生適時澄清自己的想法或說法，教師對於核心素養的理解充分反映在課堂教學實踐上。本研究提供素養導向教學的可行作法，建議後續進行相關的研究，讓素養導向教學的樣貌更加完整。

This study investigated two experienced elementary mathematics teachers’ view on competency-based instruction and their teaching in the classroom. The teachers participated in the professional learning community established by the researcher and compiled competency-based teaching modules in mathematics for 12-year basic education. The researcher conducted the semi-structured interview with the teachers as well as analyzed the teaching modules to learn their understanding of the competency-based curriculum. Research findings suggest that the case teachers’ idea of the competency-based curriculum include five of the nine competencies proposed by 12-year Basic Education Guidelines. When the case teacher applied the teaching modules to teach in the classroom, students’ mathematical thinking was the core of the teacher’s teaching. She used classroom discourse well to explore students’ ideas, invited them to participate in the mathematical discussions, and asked students to clarify their points of views. The teachers’ understanding of competency-based curriculum refl ected in their instruction. This preliminary study reveals a way of competencybased instruction. Subsequent studies are suggested to conduct to uncover the whole picture of competency-based instruction.