This multiple-case study discusses Connecticut public preschool teacher's mathematics instruction practice and preparation across socioeconomic settings and divergent District Reference Groups. Through the use of qualitative methods of classroom observations, interviews, and document review this multiple-case study explored the mathematics practice and preparation of four Connecticut preschool teachers. In addition, this study reviewed Connecticut College and University syllabi for three programs of required coursework in mathematics instruction for preservice preschool teachers. This study demonstrated the preschool teachers had limited preservice and in-service training in preschool mathematics instruction. Preschool teachers in this study focused mathematics instruction primarily on counting. The Connecticut College and University syllabi reviewed in this study demonstrated a wide variation in preservice training in preschool mathematics instruction. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]