Many people believe in the value of outdoor experiential education opportunities such as organized camps for youth, but few instruments have been developed to measure the central youth development outcomes of camp. The purpose of this paper is to present the psychometric properties including the internal consistency and validity of scales designed to measure youth development outcomes from camp experiences. This instrument was called the Camper Growth Index-Camper (CGI-C). Data collected in a pilot test, field test, and pretests confirmed constructs in four major domains: positive identity; social skills; positive values and spirituality; and physical and thinking skills. Comparisons with other data collected from camp directors, parents, and staff provided supporting evidence for CGI-C's validity and reliability. Applications of this instrument as well as improvements and extensions are discussed.