We analyze the design and implementation of a learning milieu around the topic of nutrition. This local curricular design was part of a larger project aiming at developing a curriculum for 7 grade students, inspired by the tenets of critical mathematics education. The design propitiated interdisciplinary learning in mathematics, natural sciences and computer science. It also involved in a direct way the students’ social, cultural and political context, as a way to contributing to the education of democratic and critical citizens.