There is a wide diversity of approaches to solving problems in the teaching of mathematics. In particular, the meaning of “problem solving” differs between theory and practice. In the teaching of higher mathe¬matics, problem solving is frequently used in single variable differential and integral calculus, as indicated by course contents and the number of university programs that include it in their curricula. We therefore investigated the ways in which mathematics teachers use problem solving in the teaching of single variable differential and integral calculus. A questionnaire was applied to teachers with experience in teaching sin¬gle variable differential and integral calculus from the Universidad de Costa Rica, the Universidad Nacional de Costa Rica, the Instituto Tecnológico Costa Rica, and the Universidad Estatal a Distancia. The results reveal contradictions between teachers’ conceptions of what a mathematical problem is and their implementation of problem solving in the classroom
