How early should labor market exposure start? Internships become an essential element of numerous school and university curricula, justified with an anticipated improvement in later occupational choices and job placements. For high school students there is, however, little evidence that short-term impacts are positive. This study evaluates a unique youth labor market pilot initiative. Over 50 companies have been mobilized to host high-school students who were randomly selected for firm visits. During then received on-the-job introductory trainings on work and hiring practices. Eventually, students’ subjective beliefs were updated. Expectations of entry level wages dropped by over 12% as compared to the control group. The company- student match was random within geographical proximity, allowing to rule out further self-selection into firm choices and estimating sector-specific effects. Students adjusted their occupational preferences, self- perception, and grades in line with the labor market requirements. Role models and parental background play an important role for female students’ occupational preferences, who are also less likely to dropout of school. The study adds to a literature stressing that when information interventions are implemented at an early yet very decisive age, the average impacts on beliefs and educational performance can be considerable.