A study was conducted to analyze and compare two elementary literature-based thematic curriculum units. A broad set of framing questions developed by a team of researchers representing six subject areas was used with a particular focus on the extent to which the two units would likely promote understanding and appreciation of literature and the extent to which writing was used to enhance such understanding and appreciation. Each unit was examined for its coherence, which included appraisal of the theme's potential, how the theme was developed throughout the unit to enhance and support literary understanding and appreciation, the kind of knowledge promoted, and the ways in which activities and writing assignments were complementary. Results showed that: (1) because the "Survival Tales" focus unit discussions and writing activities, it fosters a deeper understanding of the literature than does the "On the Edge" basal unit whose theme is not developed as coherently; and (2) the "Survival Tales" focus unit structure provides multiple opportunities for interaction using the four language modes in authentic reading and writing tasks, giving students a chance to make personal, social, and academic/metacognitive connections. Results indicated that teachers need to choose resources for literature-based units well and consider seriously the power of the theme for developing literary understanding and appreciation. (PRA)