The benefits of active music participation and training for cognitive development have been evidenced in multiple studies, with this link leveraged in music therapy approaches with clinical populations. Although music, rhythm, and movement activities are widely integrated into children's play and early education, few studies have systematically translated music therapy-based approaches to a nonclinical population to support early cognitive development. This study reports the follow-up effects of the Rhythm and Movement for Self Regulation (RAMSR) program delivered by generalist preschool teachers in low socioeconomic communities. This randomized control trial (RCT) involved 213 children across eight preschools in disadvantaged communities in Queensland, Australia. The intervention group received 16-20 sessions of RAMSR over 8 weeks, while the control group undertook usual preschool programs. Primary outcome measures included executive function (child assessment of shifting, working memory, and inhibition) and self-regulation (teacher report), with secondary outcomes of school readiness and visual-motor integration. Data were collected pre- and post-intervention, and again 6 months later once children had transitioned into school. Results demonstrated significant intervention effects across the three time points for school readiness (p = 0.038, n[subscript p] [superscript 2] = 0.09), self-regulation (p < 0.001, n[subscript p] [superscript 2] = 0.08), and inhibition (p = 0.002 n[subscript p] [superscript 2] = 0.23). Additionally, the feasibility of building capacity in teachers without any music background to successfully deliver the program was evidenced. These findings are important given that children from low socioeconomic backgrounds are more likely to need support for cognitive development yet have inequitable access to quality music and movement programs.