In this paper I examine the formation of post-16 choices over 3 years among higher achieving students with respect to enrolment in post-compulsory science courses. Transcripts from four interviews carried out over 3 years with 72 secondary school students were qualitatively analysed. Students were found to shape their choices for science in a variety of ways across time. The situation regarding science choices hinges on far more dynamic considerations than the stereotypical image of the potential advanced science student, committed to becoming a scientist from an early age. There is an interplay of self-perception with respect to science, occupational images of working scientists, relationship with significant adults and perceptions of school science The findings are informative for science educators and for career guidance professionals who may need to take into account the complexity of young people's choices.