In tropical developing countries, the considerations of energy efficiency and quality of school buildings are minimal, compromising the minimum internal comfort. This paper explores the effects on thermal comfort and energy generated by performing parametric variations on the typical configuration of naturally ventilated classrooms in tropical Costa Rica. Using dynamic simulations by the software Design Builder, weather data and surveys of comfort, classrooms with the same design pattern in three locations prone to overheating were analysed. Effects on energy demand and the operative temperature of the enclosure by varying bioclimatic parameters of passive cooling and solar control were reviewed. The results indicate that certain configurations can optimize the performance of the typology of the cases studied, generating the possibility of applying these design parameters to new configurations of classrooms to be built in the area. The impact of choosing appropriate design considerations and the use of simulation tools to verify building performance is demonstrated. In addition the combined potential of using passive cooling and solar control to achieve favourable thermal conditions for the user and to solve an energy demand improvement of school buildings was proved.