For centuries, scientists have studied the invisible aspects of the physical world---air, electrons, bosons---by conducting experiments and developing new methods to measure them. Psychological science is a field in which researchers use the scientific method to study how the mind works. The ways in which humans think, reason, and learn is not directly observable, so scientists need to figure out how to design experiments and develop new methods to measure and study these mental processes. Needless to say, the informativeness of an experiment critically depends on its design. But what makes an experiment informative? nHaving first-hand experience in the actual research process is a powerful way to gain a deeper understanding of the basics of experimental methods. In particular, studies with young children often require careful considerations of experimental confounds and noisy measurements, making them ideal (and challenging) test cases for acquiring the fundamentals of experimental design. This course is an advanced, lab-based research course designed to provide an immersive experience of how to investigate the developing mind. The course will take you all the way from the design and implementation of an experiment, to the analysis and communication of its results. nIn this course, students will design a replication/extension of prior work in cognitive development, and conduct studies with children (at Bing Nursery School) as well as adults (within laboratory settings or online). Students will be provided with a general experimental context and potential dependent measures, and will develop their own studies in teams. The course will involve some lectures but it will mostly be a bootcamp-style workshop where students and instructors work together. Evaluation will primarily be based on presentations and final paper, along with a few other smaller assignments. Students should expect to spend a significant amount of hours outside of the classroom to collect their data. Instructors will expect students to have a basic understanding of statistical analyses and be comfortable with basic programming in R as well as interacting with children.