This paper describes findings from a blocked randomized design (BRD) field study conducted to examine the "Next Generation Preschool Math" (NGPM) program's implementation in preschool classrooms and promise in improving young children's mathematic learning. NGPM integrates traditional preschool activities with developmentally appropriate technology to support teaching and learning. During development, an evidence-based curriculum design framework and iterative development processes were employed (i.e. design-based research). Research questions guiding this research include: (1) Does experiencing NGPM impact young children's mastery of subitizing and equipartitioning?; (2) Can the NGPM units feasibly be implemented in preschool classrooms?; (3) Does experiencing the NGPM unit 1 impact young children's mastery of subitizing?; (4) Does experiencing the NGPM unit 2 impact young children's mastery of equipartitioning?; and (5) Does experiencing the NGPM intervention improve general mathematics knowledge? The study took place in early childhood education centers in the New York City and San Francisco metropolitan areas. A sample of 16 teachers from different early childhood education centers that serve low-income children participated in the study. Approximately 8-10 children (169 children total) were randomly selected from each classroom to participate in the mathematics assessments. A set of research-based activities were developed to introduce and help young children learn the important, but rarely taught, topics of subitizing and equipartitioning. These activities included both physical manipulatives and innovative tablet-based games that complemented each other. Study results provide preliminary evidence that NGPM: (1) improves preschool children's understanding of unit-specific mathematics content; (2) was feasible to implement in preschool classrooms; and (3) left teachers wanting additional units. A table is appended.