Based on the Language Experience and Awareness approach, the Literacy 1–2–3 (L1–2–3) was designed for use in the Language Arts Window in a constructivist teaching/learning environment in Jamaican primary schools. Based on a review of studies on L1–2–3, this paper examined the extent to which characteristics of the innovation, local characteristics, and external factors impacted the effectiveness of its implementation. Findings from these studies reveal that fidelity implementation of L1–2–3 was not achieved, partly on account of resource constraints, inadequate training of the teachers and principals, and unilateral decision-making in the top-down approach to curriculum change.