It seems counter-intuitive to try to learn to sail while sitting in a classroom – but as Europeans began to venture regularly across open oceans in the 16th century, navigation became much more complicated. In order to transmit the theory behind celestial navigation, states established centralized schools and entrepreneurs offered lessons in their living rooms. Unfortunately, few records of the student experience survive. Drawing on her recent monograph, Sailing School: Navigating Science and Skill, 1550-1800, Margaret Schotte will offer a glimpse into a nautical classroom in Dieppe in the 1670s. Thanks to the fortuitous survival of records from Jean-Baptiste Colbert’s favourite teacher, Abbé Guillaume Denys, and the bright and ambitious student Jean-François Doublet, it is possible to gain insight into how early modern sailors learned the science of navigation. Which elements of the curriculum were most important, how did student-mariners use diagrams and instruments, and how did they study for their exams? The story of Doublet and Denys reveals the route by which theoretical classroom knowledge became applied seaborne skill.