The aim of the study was to compare two samples of sixth-grade Spanish primary students on coordination of writing processes measured by online or direct retrospection techniques and writing products. One group was comprised of 81 students with learning disabilities (LD), the other was made up by 80 typically achieving students. The results showed that students with LD spent more time on the task, but this generally included more interruptions and less involvement in editing, revising, reading, or changing the text. However, the findings did not highlight differences between the two groups with regard to the planning process. As for the modulation variables of writing, students with LD displayed less self-knowledge and self-regulation in composition writing, with higher writing self-efficacy beliefs than typical students. These factors probably influence the resulting texts, which showed poorer quality, structure, and coherence. The relationship between these types of variables is complex and should be explored further. This study highlights the theoretical and practical importance of studying the online processes that are developed in the composition writing of primary LD students. (Contains 6 tables and 2 figures.)