Drawing on a larger study on "Gender practices and violence between peers: the stakes of mixed-sex education", this paper examines the methodological challenges specific to carrying out ethnography in an elite high school. The researcher's subjective experience in the field reveals the power dynamics at play in the elite setting. We also examine how interdisciplinary collective analysis of the observation journals unveils less-examined challenges to conceptualization in the research process. We call for the heuristic value when contradiction and subjectivity are acknowledged and implicated both in the field and data analysis, which leads us to articulate different social identities in the elite school environment.