device. These commissions also enable people to learn while working at the Exploratorium and to discover how to translate their ideas and knowledge into instructive exhibits. In addition, people from distant universities and museums come and spend time at the Exploratorium teaching us about what they are doing, and learning what we are up to. Historians of science, from Stanford
and Berkeley, have written materials for us and planned some of the exhibits. Journalists have become our writers. K.C. Cole, for example, has written for us catalogues that are virtually short textbooks on light and vision and other matters. She too has become a teacher.

In short, one of the most important roles that the Exploratorium has assumed is that of providing rewarding and important opportunities for all manner of people,from the general populace, from the professions and from other kinds of institutions to become teachers as well as learners. I am convinced that what I observe to be happening at the Exploratorium is typical of what happens or what can happen at all manner of museums and centers. But these opportunities for teaching and learning do not necessarily just happen. They require an openness on the part of the staff to the needs and ideas of other people and other groups as well as a continuing devotion to the improvement of one's own pedagogy through exhibit development, through written and graphic material, through films, books, lectures, through what is sold in the store, and importantly through the spirit of the operation and organization of the exhibits. All of these matters have to be carefully thought out and arranged. It is wrong, therefore to talk about the museums as providing "informal" education. Much of what they do must be formalized and disciplined. A museum does, it is true, provide the props and materials that can enable all kinds of people and groups to manage their own education, whether formal or casual. And a museum, unlike a school is not, as I mentioned at the outset, concerned with certification. Nobody either gets a degree or a black mark as a result of a museum visit, and nobody really keeps track of each individual in
the sense that he or she is kept track of in school. But museums do provide most splendid and rewarding opportunities for teaching and learning. But if the museums together with all other educational media, the libraries, television, magazines and books, are really going to join forces to promote public education, then I think it is more important than ever that the role of certification not be as dominant in the overall notion of public education as it has come to be. If the learning is done by the learner for learning itself and the teaching by the teacher is done for the satisfaction of communicating what they know and love, then it will be possible to develop a really expanded view of public education that includes not only the classroom but also the conglomerate of adjunctive learning and teaching resources that we are in the process of creating.