Strategies are actions and behaviours used by the writer to solve problems in the writing process. These actions and behaviours reflect four clusters: meta-cognitive, cognitive, social, and affective processes. The goal of the overall study with 352 children was to check the effect of strategy usage on written output. Three research windows were opened to study strategy usage: all participants answered a self-report Likert-type Writing Strategies Questionnaire (WSQ). About half of them (n=187) wrote a free composition which was graded. About 10% of the participants (n=31) were engaged in an in-depth Writing Strategies Interview (WSI), and a Writing Think Aloud Procedure (WTAP). Correlations among the three measures validated the theory-based clusters. Participants who reported high use of affective strategies scored the highest on the composition. Overall the findings indicated no different distribution of use of strategies between Arab and Jewish children, and no difference in composition scores. Finally, we present an in-depth qualitative analysis of six Arab and Jewish children who portray the use of the four strategies, and discuss the contribution of the use of strategies to theory and practice in the field of writing.