Eighty 14-year old secondary school boys and girls from four different types of schools within Trinidad and Tobago's stratified secondary school system responded to open-ended questions concerning their attributions for future development. Informal interviews were also held with principals and vice-principals of the participating schools in order to obtain information on the curricular and co-curricular activities of the schools. The assumption was that adolescents from the different schools in this study would have been exposed to different kinds of opportunities, knowledge and skills over a period of three years. It was further assumed that the difference in their experience might be reflected in the kinds of casual attributions to future self-development they make. Results show that pupils from seven-year schools and from single sex schools identified ability, effort and strategy as attributions for attaining self-development more often than did other subjects from other schools. Attributional responses for the pupils from seven-year schools were more often characterized by inner locus of control. It appears that the seven-year single sex schools provided curricular and co-curricular activities which encouraged pupils to make efficient casual attributions for self-development.