Background: Teacher resistance is sometimes cited as a barrier to implementing Breakfast in the Classroom (BIC), an approach to school breakfast in which students eat at their desks after the school day has begun. Given their role in serving breakfast with BIC, teacher perceptions may be critical in implementing an effective BIC program. Methods: K-5 teachers (N = 249) in an urban, low-income school district completed an online survey that assessed their expectations of BIC (retrospectively), perceptions of its benefits and challenges, and current program satisfaction. Descriptive statistics, Pearson's correlation tests, and multiple regression analyses were performed. Results: Most teachers (64%) whose students were currently receiving BIC were satisfied with the program overall, and 81% of teachers agreed that: (1) BIC should continue; and (2) is worth the effort. The most commonly identified problem was lack of breakfast variety and healthfulness. Retrospective positive expectations were positively correlated with current program satisfaction (r = 0.61, p < 0.001), although overall post-implementation perceptions are much more positive. Additionally, the perception that BIC improves students' health is related to higher satisfaction with BIC. Conclusions: Focusing on the health implications of BIC may be important to implementing new BIC programs.