There is strong evidence that teaching planning strategies before writing is an effective way to enhance young students' written speech. According to Pressley and Afflerbach (1995), learning strategies are the set of thoughts or behaviors that one adopts to facilitate the learning process and can be used before, during and after teaching. Based on multiple sources of information, Graham and Harris (2009) suggested that teaching planning strategies and sentence combination are effective teaching practices for teaching written language. More specifically, regarding the effect of planning teaching on students' written performance, students write texts of better quality and greater scope (De La Paz & Graham, 2002; Graham & Harris, 2000). However, little is known about the specific results and benefits of teaching these strategies. In particular, the teaching community is less familiar with the results of research on teaching planning strategies as well as whether students put the planning stage into practice before they start producing written texts. It was therefore considered, particularly interesting to study this part of planning in the Greek educational reality, though research on planning and the impact it has on student’s writing.