This chapter presents aspects related to inclusion, landscapes of investigation and the perspective of deficiencialism. These ideas are based on a Master’s study of data produced in an elementary school classroom in the city of Rio Claro, in the state of São Paulo (Brazil). In this classroom, mathematical tasks from the perspective of a landscape of investigation were developed. We present a brief contextualisation of the research, methodological aspects and theoretical assumptions on inclusive education, as well as some of the children’s dialogues during the development of the tasks. As a conclusion, we present considerations on the relevance of the landscapes of investigation approach when considering inclusion from the perspective of deficiencialism.