The impact of within-student and between-student variability in basic psychological need satisfaction on situational interest development.

Introduction: To prepare students for effective workplace-based learning and cooperation, it is necessary to have insight into students' basic psychological need satisfaction and interest development over time. Methods: The framework of self-determination theory was used to conduct a field experiment, situated within a project-based cooperative learning setting, involving 169 students enrolled in higher secondary vocational education and training. These students were enrolled in a hands-on business administration and control specialist project, which required working in small learning groups. During this six-month project, students were repeatedly asked to complete the Quality of Working In Groups Instrument, an on-line measure of how strong the feeling-related need experiences of competence, autonomy, relatedness, and situational interest are fulfilled. Results: The unconditional means model showed that within-students' variability in psychological needs and situational interest (varying from 51 till 84%) was huge over time. Furthermore, multi-level growth curve modelling showed that students' growth in situational interest was positively predicted by students' initial need fulfilment of autonomy and relatedness and by students' growth in competence and autonomy satisfaction over time. Discussion: In line with self-determination theory, the findings underscore the importance of taking the basic psychological need satisfaction of students into account, tapping both between-students' and within-students' variability over time. To prepare vocational students for workplace-based learning, learning environments have to monitor, support, and fulfil students' psychological needs and situational interest over time.