educators typically design such experiences over time and make gradual improvements based on how learners respond. Not surprisingly, the design principles that emerge from the work of seasoned informal educators align in many ways with findings from research on learning.
Studies of experts and novices provide insight into what it means to have deep and flexible understanding. Experts in a particular domain are people who have deep, richly interconnected ideas about the world. They are not just good thinkers or people who are exceptionally smart. Nor are novices poor thinkers or not smart. Rather, experts have knowledge in a specific domain—such as chess, waiting tables, chemistry, or tennis—and are not generalists. However, experts do not just know “a bunch of facts.” In fact, having expertise in a topic means that knowledge is organized into coherent frameworks, and the expert understands the interrelationship between facts and can distinguish which ideas are most central. This kind of deep but organized understanding allows for greater flexibility in learning and facilitates application across multiple contexts.
Research has documented how development of expertise can begin in childhood through informal interaction with family members, media sources, and unique educational experiences.4 In fact, from early childhood onward, humans develop intuitive ideas about the world, bringing prior knowledge to nearly all learning endeavors. Children and adults explain and hear explanations from others about why the moon is sometimes invisible, how the seasons progress, and why things fall, bounce, break, or bend. Interestingly, these ideas or assumptions about how the world works develop without tutoring, and people are often unaware of them. Yet they often influence behavior and come into play during intentional acts of learning and education.
Thus, a major implication for thinking about informal science learning is that what learners already understand about the world is perhaps as important as what one wishes for them to learn through a particular experience. Accordingly, efforts to educate should focus on helping learners become aware of and express their own ideas, giving them new information and models that can build on or challenge their intuitive ideas.
Another important feature of experiences that support learning is providing prompts that guide individuals to reflect on their own thinking. This ability