This paper, by Evan Keislar and Lee Shulman (best known for advancing PCK, among many other things), takes a critical look at what has been considered a hot topic in science education for the past several decades - "discovery learning." Written in 1966 in the book Learning by Discovery: A Critical Appraisal, the authors bring up several issues with "discovery learning" (equated with the more recent "inquiry learning") and the role of teachers, curriculum developers, and education researcher in mediating this concept in relation to education.A few of important points came to mind in my reading...First, the authors acknowledge that teachers have a tendency to overgeneralize research findings in relation to discovery learning. If a study suggests that discovery learning is no more effective than direct instruction, some will use this as justification for teaching solely by direct instruction. That said, the conditions under which direct or discovery approaches to teaching and learning occur really matter. Some of the most important factors influencing the type of approach to use are the subject matter, the maturity of the student(s), the prior knowledge and experiences of the student(s), and space and time constraints of the learning environment. Like many debates, there is a false assumption that either discovery or direct instruction is best in all situations; the authors suggest here that it might be the sequence of these methods used along a continuum that provides the best instruction in a given domain. Curriculuar development deals with the "oughts" of education - what ought we teach, and how ought we teach it. When we choose and describe learning objectives, we need to be aware of the form that they take. On one hand, they can be purely behavioral (ex. The student can add 2- and 3- digit numbers) or they can take an open-ended form (ex. The student will have an appreciation of numbers). The difficulty in taking one approach or the other is that they both have disadvantages. A set of behavioral learning objectives seems to pigeonhole students as learning machines that can churn out the desired outcome. A set of open-ended learning objectives cannot be assessed using traditional tools. I've come across this difficulty working on standards documents, and my experience tells me that it is not easy to find a balance. There is a delicate balance between writing objectives that prescribe specific ways of teaching and learning and those that allow for the improvisation that occurs in the classrooms of seasoned teachers. Finally, psychological studies of learning must explore what is meant by "discovery." Discovery of what? By whom? For what purpose? Does this happen internally in the learner's mind, or does that even matter (to take a behaviorist approach)? Educational psychologists have theorized and argued about this over the past several decades, and we are far from consensus. That said, there are some promising approaches; the authors mention computer learning environments as a potentially fruitful tool for studying learning - an area that I am currently pursuing. In sum, a good paper for science educators and education researchers, written by some top minds in the field, on a topic that continues to be negotiated in the science education domain.