Los puntos clave no están disponibles para este artículo en este momento.
Deborah Stipek, Rachelle Feiler, Denise Daniels, Sharon Milburn, Effects of Different Instructional Approaches on Young Children's Achievement and Motivation, Child Development, Vol. 66, No. 1 (Feb., 1995), pp. 209-223
Stipek et al. (Wed,) studied this question.