In this research, an understanding about scholar interdisciplinarity and project working is brought, aiming at showing that the last one is an alternative methodological to promote an interdisciplinary educative practice. Therefore a pedagogical proposal was built to implement interdisciplinarity in Science and Mathematics Education in High School. It is exposed the theoretical syntheses, analysis and discussions concerning the pertinence and possibility to implement the proposal studied by the teachers and pedagogical staff in a public High School in the State of Paraná, Brazil.