The following study was developed to investigate the development of writing skills in second and third grade students. The recent emphasis on writing, specifically writing in multiple genres, made in the Common Core State Standards (CCSS, 2010) has increased the need to further understand how students write. The NAEP (2002) reports that approximately 77% of fourth grade students have only a general grasp of writing. Despite this poor performance, the Common Core State Standards (CCSS, 2010) have increased the expectations for student writing. The goal of this proposed dissertation, using an holistic literacy perspective, is to shed light on differences in how students write in informative and opinion genres, which skills predict writing outcomes, the extent to which reciprocal effects between writing and literacy are present, and what type of student profiles exist within the classroom. It was found that students received lower scores on opinion writing compared to their informative compositions. It was also found that better reading comprehension was associated with better writing performance in both genres. High vocabulary ability predicted higher opinion essay scores and better performance on a behavioral regulation task predicted better informative essay outcomes. Reciprocal effects between writing outcomes and literacy skill were found, with higher opinion writing scores predicted higher vocabulary outcomes. Finally, students appeared to fall into four latent profiles: high achievers, average achievers, struggling students, and a group of students who have average literacy skill but scored extremely poorly on the opinion essay task.