This research article from the Journal of Research in Science Teaching investigates the effectiveness of an integrated science and literacy approach at primary school level. Teachers in 94 fourth-grade (Year 5) classrooms in one US Southern state participated.
Half of the teachers in the study taught an integrated science and literacy unit on light and energy, which was designed using a curriculum model that engages pupils in reading text, writing notes and reports, conducting first-hand investigations, and frequently discussing key concepts and processes to acquire inquiry skills and knowledge about science concepts. The other half of the teachers taught a content-comparable science-only unit on light and energy and provided their regular literacy instruction.
Results of the study showed that pupils in the integrated science and literacy group made significantly greater improvement in science understanding, science vocabulary, and science writing. Pupils in both groups made comparable improvements in science reading.
Source: The impact of an integrated approach to science and literacy in elementary school classrooms (2012), Journal of Research in Science Teaching, 49(5)