Some claim that the number of students in a classroom is the most important factor affecting the quality of education. But the empirical evidence is not at all conclusive. In fact, students in countries like Japan produce higher test scores although classes are quite large.
The key to solving the “class-size” puzzle is the public good nature of classroom education. As with other public goods, such as roads, classrooms can suffer congestion. Classroom congestion is caused by student misbehaviour. Misbehaving students produce what economists call “a negative externality” borne by the rest of the class.
Some attribute public school student misbehaviour to the quality of teachers claiming that if schools can attract better teachers with higher salaries, for example, the increased cost can be more than offset by larger classroom size and higher educational output. However, private schools tend to pay teachers less than public schools.
The real problem, say some analysts, is that public schools, unlike private ones, are required to educate any student, short of violent criminal misbehaviour. Since many public schools do not allow teachers to use effective methods of controlling students such as corporal punishment, isolation and ostracism there are few ways teachers can maintain discipline.
Source: The Bad Apple Principle, Economic Intuition, 2001; based on Edward P. Lazear, Educational Production, Quarterly Journal of Economics, August 2001.
For more Economic Intuition research summaries http://www.economicintuition.com
For more on Effects of Class Size http://www.ncpa.org/iss/edu/
FMF Policy Bulletin\15 August 2002
