This thesis aims to elucidate the influences that determine the extent to which the National Science Curriculum of Trinidad and Tobago, as presented by teachers, engages students as critical thinkers. The interpretation of critical thinking is seen in terms of an emancipatory paradigm which leads to social justice. The work takes the form of a case study completed at a mixed gender government secondary school. The context is set within an education system that has come out of a colonial history and where critical thinking is seen as important for the economic advancement of the nation. However, the level of success necessary for achieving this advancement is not seen as being actualised within the present educational regime. A qualitative approach was taken in which critical theory and postcolonial theory were employed in establishing the nature of the power relations at play within this setting. The methods included content analysis of curriculum documents, exercise books and textbooks, lesson observations, focus group interviews with students from Forms 1 to 5 based on a video clip stimulus and structured interviews with teachers. The interviews were all subjected to NVivo coding to determine the themes related to the research questions.