Australian students' performance on national and international literacy assessments has declined since 2000, while teachers in contemporary classrooms contend with conditions of increased complexity and uncertainty. In July 2017, the Australian Government commissioned a panel of experts to provide advice on how to improve Australian students' achievement and school performance. The panel concluded that Australian schools must support every student to realise their full learning potential through an increased emphasis on personalised student learning and collaborative teacher practices. This paper outlines a case study of complexities and influences in enabling and constraining a local curriculum innovation in literacy that sought to personalise learning and promote teacher collaboration in conditions of constant change and disruption. Named "Literacy Toolbox," this initiative was developed by Year 7 and 8 literacy leaders at a Tasmanian secondary school to increase student agency and enhance teaching around a model of deprivatised or shared practice. The findings provide insight for education researchers and schools regarding the challenges and opportunities of attempts to enact personalised learning and co-teaching in the current context.