The advent of smart or functional 3D printing (3DP) materials ("four-dimensional (4D) materials") represents one important development toward addressing current limitations in medicine, aerospace, and other fields. Here, we report on how the ring opening copolymerization (ROCOP) of readily available and well-known anhydrides and epoxides may be used to produce a library of polyesters that are capable of being leveraged in thiol-ene photopolymer resins for processing by stereolithography or digital light processing. These polyesters display a 4D behavior (shape memory), can be processed into complex 3D structures readily, and display robust mechanical properties including elastic moduli greater than 600 MPa (with corresponding strains at break of 52.5%). These materials, with their advanced properties and robust mechanical behaviors, represent a significant advancement in the quest for 4D printing materials.