All Other Things Being Equal: Acquisition and Transfer of the Control of Variables Strategy

Abstract

The ability to design unconfounded experiments and make valid inferences from their outcomes is an essential skill in scientific reasoning. The present study addressed an important issue in scientific reasoning and cognitive development: how children acquire a domain-general processing strategy (Control of Variables Strategy or CVS) and generalize it across various contexts. Seven-to 10-year-olds ( N ϭ 87) designed and evaluated experiments and made inferences from the experimental outcomes. When provided with explicit training within domains, combined with probe questions, children were able to learn and transfer the basic strategy for designing unconfounded experiments. Providing probes without direct instruction, however, did not improve children's ability to design unconfounded experiments and make valid inferences. Direct instruction on CVS not only improved the use of CVS, but also facilitated conceptual change in the domain because the application of CVS led to unconfounded, informative tests of domain-specific concepts. With age, children increasingly improved their ability to transfer learned strategies to remote situations. A trial-by-trial assessment of children's strategy use also allowed the examination of the source, rate, path, and breadth of strategy change.

In pursuit of knowledge: Comparing self-explanations, concepts, and procedures as pedagogical tools

“…By contrast, the transfer problem formats remained unfamiliar to the children at posttest, so had to be solved by applying or adapting procedures learned during the interventiona standard approach for measuring transfer (e.g., Atkinson et al, 2003;Chen & Klahr, 1999). Children were encouraged to show their calculations when solving the problems.…”

Hands on what? The relative effectiveness of physical versus virtual materials in an engineering design project by middle school children

“…Domain-general knowledge, often referred to as ''process skill,'' includes knowledge that transcends any specific branch of science, such as knowledge about the relation between theory and evidence (Kuhn, 2002), or about the procedural and conceptual basis for the design and interpretation of experiments (Chen & Klahr, 1999;Masnick & Klahr, 2003). Domain-specific knowledge includes facts and understanding about particular domains, such as physics, chemistry, or ecology.…”

“…For example, Cells A and B were compared in a series of investigations by Klahr and colleagues (Chen & Klahr, 1999;Klahr & Nigam, 2004;Toth, Klahr, & Chen, 2000) using physical hands-on materials (physical ramps, springs, and sinking objects). The results of these studies demonstrated the relative effectiveness of direct instruction over discovery learning when teaching the ''control of variables strategy'' (CVS), a domain-general procedure for designing unconfounded experiments.…”

Science inquiry and student diversity: Enhanced abilities and continuing difficulties after an instructional intervention

“…Some researchers think of science inquiry as domain-general reasoning or heuristics (e.g., Chen & Klahr, 1999;Klahr & Dunbar, 1988;Kuhn, 1989;Kuhn, Garcia-Mila, Zohar, & Andersen, 1995;Kuhn, Schauble, & Garcia-Mila, 1992;Zimmerman, 2000). This work centers on two key questions: (1) Can children control variables in controlled experiments?…”