Environmental education program evaluation in the new millennium: what do we measure and what have we learned?

We conducted a systematic literature review of peer-reviewed research studies published between 1999 and 2010 that empirically evaluated the outcomes of environmental education (EE) programs for youth (ages 18 and younger) in an attempt to address the following objectives: (1) to seek reported empirical evidence for what works (or does not) in EE programming and (2) to uncover lessons regarding promising approaches for future EE initiatives and their evaluation. While the review generally supports consensus-based best practices, such as those published in the North American Association for Environmental Education's Guidelines for Excellence, we also identified additional themes that may drive positive outcomes, including the provision of holistic experiences and the characteristics and delivery styles of environmental educators. Overall, the evidence in support of these themes contained in the 66 articles reviewed is mostly circumstantial. Few studies attempted to empirically isolate the characteristics of programs responsible for measured outcomes. We discuss general trends in research design and the associated implications for future research and EE programming.