School-based water, sanitation and hygiene (WASH) promotion often lacks strategies to sustain behaviors beyond the promotion period. This paper describes school community engagement, in the form of a hygiene committee to institutionalize a school-based hygiene intervention and its role in implementation and sustainability. With formative data on existing hygiene practices from four urban and rural elementary schools, we arranged a workshop to design a low cost, acceptable, and feasible hygiene intervention. We formed hygiene committees including student representatives in each of four additional schools, and piloted and assessed the hygiene intervention. The hygiene committee members' active role supported intervention facilities, materials and maintenance, and promoted targeted behaviors. They encouraged continued use of hygiene materials and provided funds to cover the cost of consumables. The teachers' commitment, student motivation, and financial cost recovery facilitated continued intervention activities. During the 14-months follow-up assessment, the hygiene committee activities were still in place in all schools. The dual involvement of teachers and students in hardware maintenance ensured hygiene intervention consumables availability, functionality, and retention in the pilot schools. The hygiene committee facilitated intervention implementation and sustained functionality. Future school interventions should consider this approach in the implementation processes and cost-recovery strategies.