This study was organized to examine the impact of a field experience for elementary preservice teachers working with young children enrolled in a summer academy focusing on early mathematics. The academy was designed to provide engaging learning experiences to support the development of early number concepts for pre-K students from an elementary school with low socioeconomic populations. Using a qualitative case study, the researchers examined the experiences of the preservice teachers through pre- and post-focus groups, daily and weekly reflections, and a follow-up interview. The results revealed an increased confidence in preservice teachers' ability to teach early number concepts when supported by a lead teacher. The preservice teachers also demonstrated growth in supporting student learning through differentiation in instruction. As teacher educators must consider the types and timing of field experiences offered to elementary preservice teachers, findings have implications for teacher preparation programs with varied field experiences.