Attracting significant attention from the media and policymakers, international student assessments are serving as pressures on and challenges for individual countries. Even so, paying attention only to publicly released rankings in international student assessments may lead to superficial interpretations of the assessment results. Simply equating the rankings with educational outcomes can be a questionable perspective because the assessment results can be interpreted differently. In this context, this article has explored student achievement in the Programme for International Student Assessment (PISA) tests in comparison with civic knowledge achievement in the IEA Civic Education Study across 17 countries. This article has also evaluated efficiency in educational processes by assessing outputs (student performance in PISA) against inputs (educational spending and learning time) directly used in the education system. These two approaches clarify that publicly released rankings in PISA change to some extent when the rankings are reevaluated by taking other factors into consideration. This implication should be allowed for in interpreting the results of international assessment and the relative rankings of participating countries.