Abstract
This study reports the existence of patterns of reasoning that are common to conceptions in different areas of mechanics. The level of generality of these patterns is also studied, showing their relationship to the general frameworks of formal thought. The chosen sample was made up of 200grade 9and 10pupils from three state schools. Questionnaires about conceptions and the TOLT (Test of Logical Thinking) were used, as well as individual interviews of a small sample of pupils. The results revealed the existence of certain causal frameworks common to different ideas with an intermediate generality level which lies between that proposed by Piaget's stage theory and the more fragmentary approach of alternative conceptions. Several conclusions about conceptual change models are derived from these results.