Predictive modeling is a cornerstone of mechanics research, including when addressing problems involving drops and bubbles. Although sophisticated modeling techniques have value, the precision that they offer can come at the cost of clarity. Here a case is made for the utility of simple mechanistic models based on our lab’s research in interfacial fluid dynamics. The talk highlights two areas of research within our group: the enrichment of microplastics and pathogens from bubble-bursting aerosols and the stain size and cooling associated with drops wicking within thin, porous structures like fabric. By combining measurements and models over enormous scales, our aim is to develop a fundamental understanding that can be generalized to provide insight into a diverse set of applications.