School trips share a significant portion of the traffic in peak hours in Colombo, Sri Lanka. Therefore, understanding the distribution of school trips among predefined origin and destination zones is important in managing school traffic. The applicability of the studies carried out in other countries to the Sri Lankan context is limited due to the socio-economic factors in the study area. This study mainly focused on identifying the distribution of home-to-school trips within Colombo, the capital district of Sri Lanka. A methodology is developed using home visit survey data to construct a travel O-D matrix for home-to-school trips attracted to the government schools located in the Colombo district, followed up by mathematical models to estimate the school trip distribution. The outcomes are presented using an O-D matrix for home-to-school trips followed by O-D desire lines. Further, the study uses multiple linear regression techniques to identify mathematical models to estimate the number of inter-zonal and intra-zonal school trips between origin-destination pairs in the study area. The mathematical models proposed in this research can be calibrated and used for other developing countries with similar school education systems for better estimations.