The objective of this work was the theoretical modeling of a construct based on teaching practice about the perception that pupils have of difficulties in problem solving (PS) in experimental sciences, specifically physics, to predict pupil performance in PS. The research was carried out with an incidental sample of second year of secondary education pupils, of 13 to 14 years in age. The pupils and their teachers were involved in a project in which PS, classroom inquiry, and Hooke's law were considered to be central. The information collection instrument was a Likert type questionnaire to investigate the various difficulties perceived by the pupils (Knowledge, Trust, Path, Interest,…) in the problem-solving processes applying Hooke's law. A theoretical model was estimated and not rejected that involved only one factor (a PS factor), with all of its variables strongly interrelated and a set of constraints represented by covariances between theoretical hidden variables. This model is a starting point from which to understand how pupils at this level perceive PS in experimental sciences.