Hi, Becky -- There are any number of approaches you could take. What kind of box are you making? A cardboard box? A treasure chest? Pandora's box? A wooden chest? Probably the easiest approach would be to assemble several cubes (flattened to have dimensions of wood or cardboard) to form the five sides of the box and another cube to be the top (or two to be the flaps of a cardboard box). You could also use the free-form modeler, starting with a square, and then about an inch from your start point, use a section to hollow out the rest of the free-form path. If you'd give us some more detail, I bet someone could come up with a more helpful response! Good luck - Dex