I will present low-order models for fluid-structure interactions in fish locomotion and comment on both active (controlled) and passive (open-loop) dynamics and stability. I will also discuss a finite dipole model. The motivation for the latter is to develop scalable models for fish schooling that account for the role of hydrodynamic coupling among the fish in a school. The finite dipole model exhibits interesting dynamics. I conclude by commenting on the advantages and limitations of such low-order modeling approach.