A constant partial elasticity of substitution production function for academic achievement is presented and estimated with nonlinear maximum likelihood methods. We find that ability and time devoted to various aspects of the learning process are the most important determinants of students' accomplishments. (Author/CTM)

Two related problems are discussed: developing a methodology which (1) will not require full commitment of a local education agency to new techniques which may be ineffective in local settings and (2) will allow graceful abandonment of a new technology that may be proved ineffective. An example is discussed. (CTM)