52). Finally, the formal operational phase (11 years – adult) demonstrates psychological growth in hypothetico-deductive reasoning, in proposing a theory, using scientific thinking as validation (Swartwood, 2012, pp. 54). The Piagetian volume conservation and prediction tasks were administered to two male adolescents who acted as experimental subjects in order to thoroughly investigate the intrinsic nature of children's cognitive development. Daniel, a six-year-old boy in kindergarten, weighs fifty-nine pounds and is three feet ten inches tall. Gabriel, a nine-year-old fourth-grader, weighs seventy-three pounds and is four feet seven inches tall. As regards Daniele, it was hypothesized that the Piagetian exercise of conservation of volume was a mechanism that presented problematic aspects. Likewise, the activity showing the prediction would apparently generate confusion and misunderstanding for Daniel. On the contrary, the