What can styrofoam be covered with to make hard surface?

Styrofoam can be covered with various materials to create a hard surface, such as fiberglass resin, epoxy, or plaster. These materials harden upon curing and provide a durable finish. Additionally, using a combination of paint and a sealant can also create a protective layer over Styrofoam. Each option enhances the structural integrity and aesthetic appeal of the Styrofoam base.