Gender equality in education can be achieved through gender mainstreaming. Through gender-responsive practices, this transformation can be achieved. This study assessed the implementation of Gender and Development (GAD) perspectives in modular instruction at Mountain Province State Polytechnic College. It aimed to identify modular instruction practices that promote gender-fair learning and challenges in mainstreaming gender perspectives and suggest measures to address the challenges. The study participants were thirty-four (34) faculty members as module developers. A descriptive research method through document analysis of the syllabi and modules was utilized to identify the gender mainstreaming practices in modular instruction. An interview and focus group discussion were conducted to identify challenges and further clarify issues in the research. The data analysis showed that course facilitators considered gender-inclusive practices in module development, indicating an awareness of gender mainstreaming. However, only a few were able to integrate GAD concepts into their modules. Also, there are pressing challenges faced by the course facilitators in facilitating gender mainstreaming practices that have given rise to a lack of commitment towards advancing GAD programs. The gender-inclusive practices and the different challenges underscore the further need to intensify mainstreaming efforts in the following areas: enabling policy, human resources, material resources, and activities.