Scholars have argued against a post-COVID return to normality on the grounds that the pandemic offers an opportunity to break with the past and imagine a different, more just future. In this analysis of pre-kindergarten teachers' reflections on teaching during COVID-19 in the state of Michigan, we take up the notion of the pandemic as a portal to consider how practices that emerged during the pandemic might be carried forward post-pandemic. Through a qualitative interview study with 25 public pre-K teachers in Michigan, we sought to understand how the pandemic altered the nature of family-teacher engagement. Our analysis led us to conceptualize teaching as an improvisational practice that was highly responsive to the circumstances and needs of families. We identified three central themes that animated pre-K teachers' work during the pandemic: supporting families through new types of "offers" (a term from improv theory), making learning accessible, and fostering collectivity by partnering with families. Teachers' practices during the pandemic reveal new avenues for conceptualizing family engagement as an improvisational practice. We draw on the principles of improv theory to outline a framework for this approach.