Writing is a demanding, multidimensional process that is, cognitively and socially, highly complex. Success in writing is vital to success in education and in the workforce. Writing is increasingly used to demonstrate learning through schooling and has the potential to contribute toward understanding and learning in the content areas. The project presented in this report identified the most important elements for the effective teaching of writing for Year 5-8 priority learners. The authors worked with five diverse schools in Auckland and Wellington. In 2016, 13 teachers participated in the project; in 2017, 15 participated. All were typically performing teachers. They inquired into their practice for its impact on student engagement, progress and achievement. We used the information collected from assessment data, observations and teacher reflection to identify what leads to positive movement. The aim was to identify the key elements for effective teaching of writing for priority learners. To do this the authors needed to identify the levers for making a real difference to engagement and achievement levels for all learners in writing, but particularly for boys, Maori students and Pasifika students. Teacher proficiency appeared to strengthen over the two years: Observations of teacher practice in 2016 indicated relatively high proficiency in two dimensions (learning goals/tasks and direct instruction) over other dimensions. Scores for these dimensions were significantly above the median for 'all scores'. This seemed to indicate that particular proficiency around these two dimensions might be associated with 5% student progress, as long as some proficiency in other dimensions was evident as well. Observations of teacher practice in 2017 indicated relatively high proficiency in four dimensions -- learning goals/tasks and direct instruction (same as for 2016), knowledge of the writer and differentiation. In addition, some teacher actions related to self-regulation appear to make a difference. The quality of teaching appears to have a direct impact on the measured improvement of writing over the course of 2016 and 2017. Measurement of student progress between T1 and T2 2016 (using e-asTTle writing) indicated progress of approximately 5% across year level, gender and ethnic cohorts. Measurement of student progress between T1 and T2 2017 (using e-asTTle writing) indicated greater progress than in 2016 -- approximately 10% across year levels, but approximately 20% amongst boys and Maori students. This is particularly good in that the 2017 student cohort was much more diverse than the 2016 cohort. [This report was written with Lliam Carran, James Robertson, Kate Watson, Linda Gendall, and Zeba Ali.]