ABSTRACT
This chapter discusses the question as to whether it important to teach and learn specific subjects. It’s an empirical question about whether the subject topic makes a difference to the effectiveness of various teaching methods. That does not mean subjects aren’t important. The question is whether the most effective way of teaching languages is similar or different from the effective way of teaching welding, from teaching chemistry? The Visible Learning program seems to de-contextualize and de-subjectify and maybe even naturalize the data collected in order to get and gather real scientific material for production of evidence. The ideal seems to be that the data is not ‘polluted’ by living subjects in complex school system, and the quest for deduction is based on a large amount of processed data. The school subjects have changed through the times.
