Affective technology is increasingly becoming common in everyday life. To better understand how teachers perceive this technology in classrooms, and the role it can have in mediating the emotions of their students, we interviewed elementary (PreK-4) teachers. Our aim was to gain insights into how to design a child-emotion companion for the classroom that is mediated by teachers. From our initial interviews, we identified four interaction themes for child-emotion companions: perceived emotions, self-report contexts, playfulness, emotional wellbeing. Our early findings show how different interactions and modalities in a classroom space may change the way children perceive and communicate their emotions, and how to improve their emotional wellbeing in a classroom. We also propose design considerations that are illustrated through a low-fidelity prototype for future child-emotion companion that are mediated by teachers.