This study used a multiple probe across participants design, replicated across two interventions and counterbalanced across participant groups to examine the effects of number sense intervention and extensive practice intervention on strategy transformation when students with mathematics learning disabilities (MLD) solved basic fact problems. In addition, the effects of both interventions on students' fact retrieval performance and generalization performance were also tested. To examine the effects of each intervention, the participants were divided into two groups and the order of the interventions was varied between the two groups. The results showed that, in general, students demonstrated a greater extent of strategy transformation and generalization after receiving the number sense intervention. However, the extensive practice intervention promoted students' use of retrieval-based strategies to solve basic facts. Findings suggested that both interventions had positive impacts on students with MLD and should be used in tandem.