Children's Epistemic Knowledge Structures: Using Pollution as a Focal Issue

Environmental problems are often interdisciplinary and broad in scope. This presents a challenge in designing effective, compelling environmental education curricula, because cognitive abilities appropriate for understanding complex and multifaceted issues develop gradually. This paper's authors conducted semistructured interviews focused on pollution with school children between the ages of 9 and 16. They used these interviews to construct and understand the children's belief structures, which the authors defined as “not only the information the children possess, but also how the different concepts used by them are related.” This concept provides one way of understanding how children may incorporate hidden elements and ideas into their concepts about the environment and how it functions.

One way of illustrating children's cognitive development is through the idea of mental models. Being able to consider multiple mental models enhances one's ability to understand a system. The paper's authors cite several studies that demonstrate the development of mental models through, for example, conditional statements, such as, “If [a] then [b].” The most rudimentary understanding occurs in the form of a conjunction: “Both [a] and [b].” The most sophisticated understanding comes later; it requires the ability to understand many different scenarios and may look something like this: “Both [a] and [b], neither [a] nor [b], [b] and not [a], but no [a] without [b].”

Previous research has demonstrated that, early in life, belief structures are largely based off of the senses and the present moment. Later, the ability to think in terms of invisible things (like microbes) and further into the past or future develops. The authors focused their research on three higher-level cognitive abilities: recognizing hidden dimensions of systems, making generalizations, and thinking temporally.

The researchers identified seven categories into which the children's responses to the pollution-focused questions fell. From combinations of those categories, the researchers assembled epistemic structures by considering how the pollution-related categories were clustered around different ages. The authors describe how the epistemic structures differ in how the antecedent (the pollutant) is connected to its impacts (consequences). As the children age and mature—and as their conceptions become more sophisticated—they begin to create more complex structures, or mental models.

For the first epistemic structure, corresponding with the youngest students, the authors did not separate the pollutant from its impacts either by time or distance. For the second epistemic structure, corresponding with the middle-age group, the students described the pollutant as separate from its impact but without a sophisticated understanding of the processes. For the oldest age group, with the third epistemic structure, the students separated the pollutant from its impacts in both space and time; rather than supposing a hidden agent for the impact, the students suggested a “disequilibrium in the amount of substances in the environment.”

The research results challenge previous theories by offering insight into the cognitive abilities of children at different developmental levels. Although not easily suggesting a pathway to immediate implementation, the findings do suggest that leveraging this knowledge for curriculum design and future research will be helpful.