Are students more engaged and do they perform better in science if their school encourages them to work on science projects, participate in science fairs, belong to a science-related club or go on science-related field trips--in addition to teaching them the mandatory science curriculum? To find out, PISA (Programme for International Student Assessment) 2006 asked school principals about what kinds of extracurricular science activities they offered their students and linked their responses with students' performance on the PISA science test. This paper reports that: (1) Around 90% of students in OECD countries attend schools that offer field trips to places where students can learn about scientific principles and concepts; and (2) In most countries, science-related extracurricular activities at school are related to better student performance, a stronger belief by students in their abilities to handle science-related tasks, and greater enjoyment of learning science. And, in many countries, this is true even after accounting for the socio-economic background of both students and schools.