We selected 60 low-achieving pupils from a sample of 263 pupils in year 2 of the primary school in order to analyse the problems of learning disabilities. We raised the following questions: 1.) whether the teachers evaluate the pupils' school performances correctly, 2.) how do the teachers and parents perceive the connection between the low-achieving pupils' cognitive abilities and their school performances, 3.) what kind of relation can be assessed between the low-achieving pupils' cognitive abilities and their school performances, 4.) what is the non-low-achieving classmates' attitude to their low-achieving peers. We used the following methods: questionnaires, pedagogical tests, traditional psychological tests. We obtained the following results: 1.) the teachers generally evaluate the pupils' school performances fairly well, but they are inclined to assume a closer correlation between the achievements in different subjects, and the teachers' knowledge of the pupils is more reliable regarding the group of pupils as a whole than regarding each of them individually, 2.) the teachers and the parents can find the reasons for the low school performances in the weaknesses of the cognitive learning abilities, 3.) the low-achieving pupils' cognitive learning abilities prove to be significantly weaker than their general intellectual abilities, 4.) their low school performance does not adversely affect social relationships between the low-achievers and their non-low-achieving classmates.