An investigation into the change in PISA 2000-2015 results of Germany and Turkey and the education reforms in Germany since PISA

The purpose of this study is to compare the PISA results of Turkey and Germany up to the year 2015 and to investigate factors affecting the academic success in each country. Especially, Germany's changes in the education system after 2000 were explored. Turkey's and Germany's reading, maths and sciences PISA scores were examined and compared. The effects of the socio-economic background, immigrant background and different school types were evaluated with regression analysis. The study was conducted with 25.536 students from Turkey between the years 2003 and 2015 and 31.108 students from Germany between the years 2000 and 2015, all of which were 15 years old. The academic success of the students in reading, math and science was defined through the PISA cognitive test, and the socio-economic background, immigrant background and school type data was taken from questionnaires from the students and schools. The results of the study revealed that Germany, in the year 2000, was under the OECD average in reading and science and just close to the OECD average in maths. In the following years, the scores increased in all fields; the science score from 2006, the maths score from 2009 and the reading score from 2012 was over the OECD average. In 2003, in the first year Turkey participated in the PISA study, only one OECD country scored below Turkey. Throughout the years Turkey's PISA scores have been under the OECD average in all fields but have increased every year until 2012. From the differences in Germany's reading, math and science scores 15-29% can be explained with differences in socio-economic background, 4-13% with differences in the immigrant background and 40-51% with differences in the type of school. The differences caused by the socio-economic background decreased over the years especially. For Turkey, 9-22% of the PISA score differences can be explained by the differences in the socio-economic background, and 25-33% by the differences in the type of school. Through out the years the differences caused by socio-economic background decreased while the differences caused by the school type increased. When considering the socio-economic background then the differences in the type of school can partially be explained in both countries.