In neo-Piagetian skill theory, a process of change in which persons use a target skill (called a shell) to guide their construction of a new skill. People use the higher-level target like an algebraic equation in action, a target with unspecified components that are used to shape and direct the development of lower-level skills. In this way, the higher-level target serves as a bridge in the construction of the lower-level components to form a new skill.
See Constructivism, Levels of analysis, Levels of development, Levels of organization, Neo-Piagetian theories of cognitive development, Shell