Average achievement scores of Latvian students in latest PISA studies are close to the OECD average but, nevertheless, the results show only a very small number of top performers in mathematics, reading and science. The percentage of students reaching the two highest levels of proficiency in Latvia is smaller than in Lithuania, the Russian Federation and other countries from the Baltic Sea region. There are signs that Latvian students from high SES families do not perform as high as they possibly could if seen in international perspective. The present research objective is to investigate the reasons for the international differences in reading scores for students from high SES families. Our research question is: Which school-level factors might help raise the achievement levels of students with a high family socio-economical background? PISA 2012 data is used to analyze the situation in a number of Baltic countries. These countries have quite minor cultural differences but relatively large differences between their average achievement scores. Our comparative analyses include Sweden, Finland, Russian Federation, Estonia, Latvia, Lithuania, Poland, Germany and Denmark. Descriptive statistics and regression analyses will be performed, and comparisons with the OECD average and national averages will be presented.