The aim of this study was to develop a tool to measure levels of mathematical knowledge gained in high school, as perceived by incoming engineering students. The study included 657 engineering students in the 2011-2012 academic year. Factor analysis was used to obtain a scale consisting of 47 items (Cronbach Alpha coefficient, 0.975). The mathematical knowledge scale consisted of five sub-dimensions (Integration, Differentiation, General subjects, Graphing and Limit) related to subjects in the high school mathematics curriculum. Engineering students were asked to evaluate their own levels of knowledge. There was a significant difference between average scale scores of students successfully completing the calculus I course during the first semester of university and those failing this course. This difference was in favour of the students completing the lesson successfully. (Contains 6 tables.)