Along with emerging literacy and numeracy, spatial skills and reasoning set the foundation for young children's school readiness and early education. This study explored introducing an innovative curriculum for promoting young children's spatial learning in Morogoro, Tanzania. Four hundred twenty-eight children from 21 schools participated; 11 schools received a seven-week educational intervention using Pattern ABC cards, while another 10 schools served as a control group. Within the intervention schools, six received a "boost" training to assist in delivering the intervention lessons. At baseline, children demonstrated low levels of literacy, numeracy, and spatial skills. The team estimated multivariate hierarchical linear models after the intervention and found that those children in classrooms with the boost performed significantly better than those in the regular intervention and control classrooms on several core spatial skills, including identification, naming, and matching to line drawings. This study offers evidence that an educational intervention featuring shapes and patterns can be delivered although it was a challenge, as it differs greatly from the typical pedagogical approach in this low-income, resource-poor environment. Greater teacher training can increase the program effects, particularly with respect to successful implementation of lessons involving less frequently taught spatial concepts and approaches.