The standard Brazilian school projects (EMEIs) were created for the Proinfância [Pro-Childhood] program to respond to the growing national demand for public schools. Unfortunately, the project disregards the Brazilian local climate, leading to an inadequate architectural design, especially in terms of energy performance. Within this context, this research aimed to assess the impact of a new geometric design and envelope proposal on the energy performance of a Brazilian school building. The study object is a standard project (EMEI) of the Proinfância program located in Pelotas, Brazil. Two distinct multi-objective optimizations were performed based on EnergyPlus coupled with the Strength Pareto Evolutionary Algorithm 2 (SPEA2), in which the objective functions were defined to minimize heating and cooling Energy Use Intensity (EUI) for different geometric designs (Base and Linear models). The design variables considered were window-to-wall ratio (WWR); thermal insulation thickness for walls and floor; solar absorptance values for walls and roof; and solar orientation. A total of 74.520 simulations were carried out, and the results indicated that the new geometric design combined with bioclimatic envelope strategies was capable of reducing 52% of the Energy Use Intensity when compared to the standard school project.