Classrooms and schools with more disciplinary problems are less conducive to learning, since teachers have to spend more time creating an orderly environment before instruction can begin. Interruptions in the classroom disrupt students’ concentration on, and their engagement in, their lessons. Results from PISA 2009 show that disciplinary climate is strongly associated with student performance. Students who reported that their reading lessons are often interrupted perform less well than students who reported that there are few or no interruptions in class.

Popular belief has it that every successive crop of students is less disciplined than the one before it, and that teachers are losing control over their classes. But popular belief has it wrong: according to data gathered in PISA 2009, the majority of students in OECD countries enjoy orderly classrooms, and between 2000 and 2009, discipline in school did not deteriorate – in fact, in most countries it improved...