“…Our results may be of interest for countries where the use of grade repetition is widespread, such as Belgium, Portugal or the Netherlands, and stresses the need to consider alternative policies, as social promotion does not seem to be an effective alternative (Darling-Hammond, 1998). Examples of alternative policies for enhancing the academic achievement of low-performing students are improving teacher practices, such as introducing looping and multi-age grouping (Leuven and Ronning, 2016;Franz et al, 2010); increasing instructional time at school (Slavin et al, 2011;Ritter et al, 2009), out of school (Jacob and Legfren, 2004) or during summer breaks (Borman and Dowling, 2006) for low-performers through individual or group tutoring methods; or making curriculums and educational systems more flexible, removing dead ends and allowing low-performers to have additional time for catching-up with their peers. As it may be seen, the implementation of most of the previous policies requires teachers to identify early students at risk (Allensworth and Easton, 2007;Balfanz et al, 2009).…”