This article reports on an exploratory qualitative case study aimed at investigating the impact of an EFL reading ability exam on the attitudes, behaviors and actions of teachers in three different settings of EFL teaching at the secondary level in Campinas, São Paulo State, Brazil. The exam is part of the entrance examinations administered by State University of Campinas since 1987. The study triangulates information collected from different perspectives and methods. Impacts of different intensities are observed in the cenarios investigated, which may be taken as evidence to conclude that the effect of this test on teaching is not deterministic.