Degradable hydrogels synthesized through free-radical chain polymerizations of macromolecular monomers are increasingly used as cell encapsulation platforms. Controlling degradation of the hydrogel is important for this application and is typically achieved by incorporating hydrolytically or enzymatically degradable crosslinkers within the gel-forming macromers, where the rate of degradation is pre-determined by the initial macromer chemistry. Here, a novel photolabile poly(ethylene glycol)-based (PEG) macromolecular monomer (PL-b-PEG-b-PL diacrylate) was used to synthesize hydrogels that degrade upon light exposure, allowing real-time and spatial control of degradation. Upon exposure to light, this macromer undergoes photolytic cleavage to release PEG. Fluorescent, photolabile copolymer networks of PL-b-PEG-b-PL diacrylate and PEG monoacrylate were created by redox-initiated polymerization (15 wt% in water). These networks were irreversibly degraded with 365nm and 473nm light to control network properties, such as stiffness, characterized with rheology and to create 3D channels to direct cell behavior characterized with confocal microscopy.