A central goal of upper elementary schools is improving students' skills to write persuasively using source materials. This study focused on three essential areas of writing at the upper elementary grade levels. First, children learned skills to read and use source materials through the web-based intelligent tutoring system for the text structure strategy (ITSS), select key ideas in the text, generate main ideas, and write summaries. Second, teacher-led instruction about planning and writing persuasive essays was delivered using the self-regulated strategies development (SRSD) model. Third, fifth-grade students mastered persuasive writing skills using the We Write tools. The We Write computer tool is a teacher-led system choreographing the roles of the teacher and technology to achieve maximum instructional impact. Teachers received practice-based professional development with coaching and modeling to implement the intervention. In a randomized trial with seven schools and their fifth-grade classrooms, this approach was effective in improving students' writing. Results show that after six weeks of text structure instruction on the web using ITSS, effect sizes on writing quality and planning were 0.30 and 0.77. After an additional 12 weeks of SRSD-based writing instruction effect size on planning quality was 1.60 and writing quality 2.29. These strong results can inform the design of technology-supported writing interventions for elementary grade students. [This is the online first version of an article published in "Educational Technology Research & Development."]