Bebras is a contest organized for schools to promote computational thinking and new tasks are developed for it every year. The contest is held online in over 50 countries around the world and its results provide a great deal of information regarding difficulty levels of particular tasks and factors influencing participants’ success in the contest. Our paper brings an analysis of such hard data in relation to statements of those participants who expressed their opinion on the difficulty of particular tasks and whose statements could be matched with their actual academic performance in the contest. Questionnaires were voluntarily completed by contestants participating in the Senior category (for the oldest participants aged over 16) from the Czech Republic.

Statistical analysis of contest results and perceived task difficulty provided new findings. There is no relationship between the proportion of participants with wrong answers to tasks and participants’ subjective perception of task difficulty. Subjective difficulty is more aptly expressed in terms of the proportion of participants who did not answer the task. The contest was perceived as being easier by those participants who achieved higher scores in it. Male participants demonstrate a higher level of self-esteem in terms of IT skills than female participants. However, female participants’ self-perceptions of their IT skills are slightly more accurate than males’. Results presented in the article could help the authors of the contest to improve compilation of contest tasks and have them included in the Informatics curriculum.