The goal of this research was to explore cognitive, self-determined learning and autonomous motivational effects in the context of a mobile science exhibition (N = 256) in Finland. The pupils were sixth-graders with an average age of 12 years 6 months. Autonomy experience, as measured by the Relative Autonomy Index (RAI), had an effect on how the pupils liked learning science both at school and in a science centre context. The more autonomous that students feel, the more likely it is that they have intrinsic motivation in learning science. The RAI also predicted momentary situational motivation. The most important enhancer of situation motivation was liking science learning at school, but this was true only among boys; nevertheless, in general, girls were somewhat more motivated by the science exhibition than boys. There was no gap between boys and girls in post-knowledge testing, suggesting that girls benefitted more from the science centre learning experience than boys. Although gender differences in the knowledge tests leveled, students having higher reasoning ability, measured by Raven, gained more from the exhibition than the others. Post-knowledge was explained most by pre-knowledge, but the overall substantial learning results were enhanced directly and indirectly by the motivational factors. The practical implication for the science centres is to offer both teachers and pupils learning materials to be used before and after the visits.