Concepts are ideas, “abstract categories or classes of meaning” (Parker, 2012: 317), such as revolution, colonialism, religion, government, representation, domestic labor, settlement or port; each of these can include many different specific instances (e.g. the French Revolution, German colonialism and Buddhism).1 Such concepts form the foundation for learning in history and the social sciences. Sometimes, students need to understand that an entity or event fits within a particular conceptual category (e.g. Germany is a parliamentary republic, workers went on strike). More often, students need to understand relations among concepts: famine in Ireland led to emigration; industrialization is associated with urbanization; governmental policies often involve tradeoffs between freedom and security. Even when these labels are omitted, the importance of concepts remains: an observation such as “Franz Ferdinand was assassinated by Gavrilo Princip” is significant only if students understand that Ferdinand was heir to the Austro-Hungarian monarchy and that Princip was a Yugoslav nationalist.
As these examples illustrate, concepts are not usually specific to a given field. Historians, geographers, economists, sociologists and others all use concepts such as urbanization, emigration, public policy and countless others. The difference between history and other school subjects is this: curricula in geography, government, economics, and so on, explicitly emphasize the meaning of concepts (i.e. students are expected to develop an understanding of population density, human rights, inflation, and so on), whereas in history the curriculum typically takes for granted that students already know these concepts. History curricula, that is, outline particular examples of diplomacy, migration or revolution, but do not usually call attention to the need to teach the conceptual meaning of diplomacy, migration or revolution.
Yet as experienced teachers know, students who lack underlying concepts will be unable to make sense of the topics they are expected to study. Those without a conceptual understanding of taxation and representation, for example, will not see why North American colonies rebelled against Britain, even when the teacher explains it; the explanation will go over their heads, and they may thus misinterpret the American Revolution as a petulant interpersonal squabble rather than a political and economic conflict (Barton, 1997). Sometimes, rather than simply failing to understand relevant concepts, students draw upon concepts they already possess, even when those do not apply to the topic at hand. Those without a concept of empire, for example, are likely to think of Han China or Imperial Mali as though they were either kingdoms or modern nation states. In order for them to understand particular empires in history, they must first understand what an empire is and how it differs from other forms of political organization.
Some people may not see this as much of a problem. Just tell students the definition of empire, or tell them to look it up for themselves, and get on with it. The problem with this approach, however, is that students do not develop conceptual understandings simply by listening to explanations or looking up definitions. Conceptual learning depends on a more involved process, one in which students compare examples and non-examples, identify common and distinguishing characteristics, create their own definitions and apply them to new instances (Larson & Keiper, 2013; Parker, 2012). History teachers, then, have to draw from both the professional literature and their own experience to identify which concepts they need to help students develop. In studying medieval Japan, for example, there is no need to teach the concept of island, because teenagers will already understand it; feudalism, on the other hand, may require explicit conceptual development—teachers cannot simply expect that students know what it means, or that they can learn it from an explanation or formal definition.
Concept development, however, takes time. A concept lesson can easily take up an entire class period, or longer. An ideally structured curriculum would take this into account and would teach students concepts in their social science classes before they needed them in history; they would learn the concept of republic in government before studying the Roman Republic in history, for example, or would learn about the relationship between industrialization and urbanization before studying the history of the eighteenth and nineteenth centuries. This kind of organization may be too idealistic, but curricula should at least give students the chance to develop an understanding of concepts and their relationships in multiple subject fields, because so few are specific to any one area. Not only would this prevent history teachers from having to develop students’ understanding of each social, geographic, economic or governmental concept they need, but it would also free them up to help students understand how some concepts have changed over time. All concepts are human constructions, and thus their meaning often is historically contingent; the concept of nation, for example, has changed substantially over the centuries (Carretero, Castorina, & Levinas, 2013). History teachers would be better able to address these changes if students had previous experience developing core understandings in other subjects (Thornton & Barton, 2010).