On average, there are about 22 students per class at primary level, but this varies from 30 or more per class in Chile and Korea to nearly half that number in -Luxembourg and the
The number of students per class increases by an average of more than two between primary and lower secondary education.
The student-to-teacher ratio in lower and upper secon-dary education is slightly lower in private than in public institutions.
This spread examines the number of students per class at the primary and lower secondary levels, and the ratio of students to teachers at all levels. Class size is a hotly debated topic in many OECD countries. While smaller classes are often perceived as enabling a higher quality of education, evidence on the impact of class size on student performance is mixed.
At the primary level, the average class size in OECD countries is about 22 students, ranging from 30 or more in Chile and Korea to fewer than 20 in Austria, the Czech Republic, Denmark, Finland, Greece, -Iceland, Italy, Luxembourg, Mexico, Poland, Portugal, the Slovak Republic and Switzerland and Estonia, the Russian Federation and Slovenia.
In lower secondary education, the average class size is 24 students, ranging from more than 35 students in Korea to 20 or fewer in Denmark, Iceland, Luxembourg and Switzerland, and the Russian Federation.
At the primary level, the ratio of students to teaching staff (with part-time and full-time teachers combined and expressed in terms of full-time equivalents), ranges from 24 students or more per teacher in Chile, Korea, Mexico, Turkey and Brazil to fewer than 11 in Hungary, Italy, Norway and Poland. The OECD average in primary education is 16 students per teacher, and 14 at secondary level (see Chart D2.3 in Education at a Glance 2010).
Across the OECD, average class sizes at the primary and lower secondary levels do not differ by more than One student per class between public and private institutions. However, there are differences between countries. At primary level, the average class in a -public institution has at least four more students than one in a private institution in Poland, Turkey, the United Kingdom, and the United States, and Brazil and the Russian Federation. By contrast, the reverse is true for Japan and Spain. At the lower secondary level, where private education is more prevalent than at primary level, class sizes are larger in private institutions in 13 countries.
Among two-thirds of countries with comparable data, class sizes tended to decrease slightly between 2000 and 2008, most notably in countries that had relatively large class sizes in 2000, such as Korea and T-urkey. By contrast, they tended to increase in countries that had relatively small class sizes in 2000, such as Iceland.
Data refer to the 2007-08 school year, and are based on the UOE data collection on education statistics admi-nistered by the OECD in 2009. Class sizes have been calculated by dividing the number of students enrolled by the number of classes. The ratio of students to teachers has been calculated by dividing the number of full-time students at a given level of education by the number of full-time teachers at that level. Data for Switzerland refer to public institutions.