or they can be unplanned and unanticipated, developing contingently on the basis of what is most valuable to the participant. In informal settings, outcomes are often guided by the learners themselves. Research can target outcomes that emerge in these experiences, not only those that are defined a priori.
Outcomes can become evident at different points in time. Short-term outcome measures have long been used to assess the impact of informal learning experiences, but these experiences can also have enduring, long-term impacts that differ from the short-term ones.
Outcomes can occur at different scales. Outcomes defined on the level of individual participants answer the question: How is the individual influenced by the experience? Most of the outcomes discussed in this chapter and in the literature generally focus at this level. But it is also useful to ask: How is the entire social group in the environment influenced? For example, did group members learn about one another, reinforce group identity and history, or develop new strategies for collaborating together? We can also define outcomes on the community scale: How does the activity, exhibition, or program influence the local community?
These assumptions regarding outcomes align with three high-level criteria that the evidence suggests are essential in the development of assessments appropriate for science learning in informal environments. First, the assessments must address not only cognitive outcomes, but also the range of intellectual, attitudinal, behavioral, social, and participatory capabilities that informal environments effectively promote (Jolly, Campbell, and Perlman, 2004; Hein, 1998; Schauble et al., 1995; Csikszentmihalyi and Hermanson, 1995). Second, assessments should fit with the kind of participant experiences that make these environments attractive and engaging; that is, any assessment activities undertaken in informal settings should not undermine the features that make for effective learning there (Allen, 2002; Martin, 2004). Third, the assessments used must be valid, measuring what they purport to be measuring—that is, outcomes from those science learning experiences (National Research Council, 2001).
Assessment must also be valid in terms of construct validity—that it measures what it purports to measure—and in terms of the ecological validity—that it aligns with the opportunities for learning that are present in the learning environment (Moss et al., in press). In light of the tendency to use conventional academic outcomes to study learning in informal settings, it is important for researchers and practitioners to carefully consider ecological validity of such measures for informal settings. Measures must ensure that the same kinds of material, social, cognitive, and other features