A tool used to cut cardboard containers, known as a case cutter, frequently causes lacerations among adolescent grocery store workers. We evaluated a safety program using a less hazardous case cutter combined with worker education. Nine supermarket stores were divided into three groups. In Group A stores, employees received new safety case cutters with education; in Group B stores, employees received education using old cutters; Group C stores were the control. Case cutting lacerations were tracked 3 years before, and 1 year after, the intervention. There were 199 cutting injuries. Cutting injury rates decreased 3.5/100,000 man-hours in Group A stores, compared to 1.5 in Group B stores and 1.6/100,000 man-hours in control stores, with a marked reduction of compensation-related injuries in A stores. Estimated cost savings for A stores were $245/year/store and $29,413/year for the chain. An intervention to decrease case cutting injuries among adolescent grocery store workers can be protective and cost-effective.