Preparing elementary-aged children to practice data science literacies is important and understudied. Our research investigates how data science curricula might be effectively designed and integrated into elementary classroom instruction. We use narrative case study methodology, focusing on a single case detailing a second-grade teacher's approach toward offering students a data science instructional unit. We qualitatively analyzed observations, journals, interviews, and artifacts to document the teacher's process. Findings suggest the importance of co-designing with peers, posing relevant problems, integrating standards and differentiating instruction, relying on everyday practices, integrating disciplines, and promoting student collaboration when practicing data literacies. Our example offers elementary school educators' practical ways to deepen children's engagement and hone data science literacies through data science instructional units.