There have been a couple of news items about the link between the practice of differentiation and student achievement (see here and here). These have been prompted by the release of TALIS; an OECD survey of teachers. Caution is needed here because differentiation and differentiated instruction mean many things to many people. For instance, differentiation could simply mean targeting teacher questions to specific children. In some versions of differentiation, students may be given different tasks due to some conception of their ‘learning styles’. However, the data from the survey relates to the specific practice of giving different students different tasks to complete within the same classroom, either because they are ahead of their peers or because they are struggling.
I have collated the data on this survey question and then plotted 2012 PISA mean maths score against it in order to produce the chart below (click for clearer view):