Social functioning and reading proficiency are critical for success in school and society. Therefore, identifying children with such problems is important. This study had 2 parts: first, a random sample of 234 elementary schools was surveyed about which instruments they use to assess reading proficiency and social functioning. Second, a systematic review of the quality of these instruments was conducted using international standards for examining the quality of assessment instruments. The survey showed that schools more often assessed and had more instruments available for reading than for social functioning. The systematic review of the assessment instruments used revealed that the psychometric qualities of many was weak or undocumented, while the dimensions of test material quality were generally good. The findings demonstrate a need for a more thorough examination of the psychometric properties of assessment instruments to be used in school.