Thesis advisor: Eric Dearing / Research has shown that parents’ number talk predicts preschoolers’ concurrent and prospective math skills; yet, there is considerable heterogeneity in parents’ use of number talk (e.g., Ramani et al., 2015). Given this, researchers are developing resources and interventions designed to encourage family numeracy (e.g., Hanner et al., 2019). Interventions, however, are based on a limited understanding of how families engage in numeracy conversations, particularly when parents are working to teach their children. Developmental researchers tend to operationalize parent talk as discrete, decontextualized instances of environmental input. In contrast, scholars using Conversation Analysis (CA) argue that understanding interactional phenomenon requires attention to how it is collaboratively and incrementally constructed through turn-taking sequences and how it allows interlocutors to accomplish social actions across stretches of interaction (e.g., Schegloff, 2007). The current study used CA to examine parent-preschooler conversations about numeracy during a home-based math intervention for which parents and children cooked together. The 30 parents—primarily middle-class, college educated parents of color— and their 3- to 5-year-old children received a cookbook with domain-general learning tips and 15 recipes. Families in the treatment condition received additional numeracy tips, some specific to the recipes provided and some broadly applicable to any recipe. Families were asked to audio record themselves cooking twice a month for three months. Results indicated that exchanges in which numeracy pedagogy was irrelevant (i.e., low-relevance pedagogy) for completing the recipe were qualitatively different from exchanges in which numeracy pedagogy facilitated children’s participation in cooking tasks (i.e., high-relevance pedagogy). While low-relevance pedagogy engaged children in rehearsing their numeracy skills, high-relevance pedagogy invited children to use their numeracy knowledge to plan and implement recipe tasks. Counting occurred primarily within low-relevance pedagogy, meaning parents’ prompts to count were disconnected from cooking. The recipes, ingredients, and cooking tools families selected shaped the affordances for numeracy pedagogy. This dissertation has implications for improving early learning interventions. / Thesis (PhD) — Boston College, 2021. / Submitted to: Boston College. Lynch School of Education. / Discipline: Counseling, Developmental and Educational Psychology.