Curriculum at the secondary level plays a critical role in shaping students’ academic preparedness, cognitive growth, and socio-cultural orientation. India’s secondary education system is characterized by curricular diversity, with multiple boards operating simultaneously. Among these, the Central Board of Secondary Education (CBSE), the Indian Certificate of Secondary Education (ICSE), and the International Baccalaureate (IB) are the most influential. This paper presents a qualitative comparative analysis of the secondary curricula of CBSE, ICSE, and IB with reference to their philosophical foundations, curriculum design, pedagogical approaches, assessment practices, and student learning outcomes. The study is based on a systematic analysis of curriculum frameworks, assessment models, and documented educational practices. The findings indicate that CBSE emphasizes curricular uniformity, academic standardization, and national integration; ICSE prioritizes conceptual depth, analytical reasoning, and language proficiency; while IB foregrounds inquiry-based learning, interdisciplinary understanding, and international-mindedness. The study argues that curriculum effectiveness is context-dependent and cannot be evaluated through a single universal standard. The paper concludes by emphasizing the importance of informed curriculum choice and policy alignment to enhance the quality and relevance of secondary education in India.