An instructional program based on a learning hierarchy and involving the addition of fractions was presented to fourth grade students in a pretest - posttest design. The results of the tests were analyzed using both Walbesser's and White's techniques for validation. There was sufficient disagreement in the results to prevent a conclusion of…

The need for an empirically defensible means of sequencing instruction appears to have been the primary motivator for research into learning hierarchies. Four methods for generating candidates for learning hierarchies were reviewed: introspection, formal analysis, observation, and statistical "fishing." Experimental transfer of training…