An effective way to improve students' mathematical knowledge is to have them construct multiple solutions for real-world problems. Prior knowledge is a relevant prerequisite for learning outcomes, and the experience of competence is a basic need that has to be fulfilled to improve achievement. In the current experimental study (N = 307), we investigated how the construction of multiple solutions for real-world problems by applying multiple (two) mathematical procedures affected students' procedural and conceptual knowledge and their experience of competence. Path analyses showed that constructing multiple solutions for real-world problems increased students' feelings of competence and affected their procedural and conceptual knowledge indirectly through the experience of competence. Moreover, students' prior knowledge affected their knowledge at posttest directly as well as indirectly via their experience of competence.