In this article, we examined the relationship between mathematics performance and metacognitive behaviors during task resolution and the selfconcept of students with and without learning disabilities in secondary education. These variables were explored in boys and girls without SEN (N= 139) and those with SEN, either in inclusive (N= 32) or special classes (N=11). In the group of students without learning disabilities in secondary education, some relationships were found between mathematics performance and metacognitive behaviors during task resolution. Self-concept, especially scholastic competence and social acceptance showed significant relationships with performance and the metacognitive measures and measures of self-concept also showed significant inter-correlation, resulting in a recognizable pattern in this group. In the groups with SEN, however, the performance was lower and neither concurred with the estimation of how well the problem was solved, nor with calibration and general metacognition. Although a correlation was found between performance and problem representation, other correlations were zero or even negative, indicating that the overall pattern was not very coherent. The inter-correlations between the metacognitive variables and measures of self-concept were generally not significant. These results question the validity of the metacognitive measures, and suggest that an approach using questionnaires may work for a group of children without difficulties, but appear less appropriate for boys and girls with SEN.