Postural management is an essential part of treating cerebral palsy (CP), but research in this area, particularly in the Middle East, is limited. This study aimed to assess how selecting the right wheelchair can affect spasticity, quality of life, and motor function in children with CP. The study included 35 children, aged 4 to 12 years, all with moderate to severe motor impairments (GMFCS levels 3 to 5). After four weeks of postural management using properly selected wheelchairs, there was a significant reduction in spasticity, as seen in improvements across key joints like the shoulders, elbows, wrists, and hips (p < 0.001). There were also notable improvements in motor function, with GMFCS scores improving significantly (p < 0.001). Additionally, the children’s quality of life scores saw a marked increase, from 3083.9 ± 206.6 to 3538.6 ± 186.9 (p < 0.001). These findings stress the importance of choosing the correct wheelchair for children with CP, as it can make a significant difference in both physical function and overall well-being. The results also highlight how important postural management and occupational therapy are in improving the lives of children with CP.