The present study approaches the issue of school achievement at gymnasium and high school levels.The participants are 366 gymnasium and high school students (medium age 16.1 years, SD 1.80) who were tested with a complex battery made of eight intelligence tests, together with Big Five personality questionnaire and Holland's Self-Directed Search (SDS). According to the model of Holland's structure of interests, it is expected that the realistic type should provide the biggest ratio of underachieved people while the social type the biggest ratio of overachieved people. The research confirms these hypotheses and opens several new directions of investigating school achievement.