Songer (1989) demonstrates the effectiveness of the continuum line for
helping students to integrate their understanding of insulation and conduction. This
study augments and extends that investigation to demonstrate that principles and prototypes
are suitable loci for the integration of groups of experiments in thermodynamics. This
study also suggests that offering students a range of loci for integrating their understanding
is advantageous, because for some students, principles would be too abstract, and for
others, prototypes would be too narrow