Two main presuppositions must be met in order for teachers to begin differentiating their instruction: (a) adequate knowledge of the subject which is to be taught and (b) a very good knowledge of each student’s characteristics, needs, strengths and so on. Consequently, the teacher can plan the lesson ahead based on what he/she is up against. Nevertheless, even though planning is an essential component of differentiated instruction, teachers must be ready to dynamically adapt and modify the learning process according to their students’ responses. Differentiation is not a recipe to be delivered (Tomlinson, 1999) and cannot be exhausted in the employment of some differentiation techniques and strategies. Differentiation, according to Koutselini, must be seen as a ‘‘contextualized teaching and learning experience in the social, cultural and political framework of both, teachers and students, that provides a non technical paradigm of instruction, which contributes to the realization of the equality in education policy.’’ (Koutselini, 2008. p. 4).