Box cutters, utility knives, craft knives and scissors work well for cutting cardboard. For kids' crafts, an adult can cut any heavy cardboard that requires sharp tools. Kids' scissors with blunt tips work fine for light cardboard, such as stiffeners from packaged shirts. Hardware stores and home improvement centers sell box cutters and utility knives, along with their replacement blades.
Box Cutter for Boxes
Before using a box cutter, put on safety goggles and remove any staples from the boxes. Slip a flathead screwdriver under each end of the staple to pry the ends up, and then pull the staple out by levering the screwdriver under the long part of the staple. Depending on the size of the box, you will need to put it on the ground or on a workbench and cut each corner from the bottom to the top to create four flat panels. If you want one flat sheet of cardboard, cut one corner along with any tape holding the box together and then unfold the box.
Utility Knife for Flat Cardboard
Make sure your utility knife has a fresh blade before you use it on flat cardboard. Wear heavy-duty leather gloves and keep your fingers clear of the blade. Lay the cardboard on a surface that won't be marred by cuts, such as a utility table or a cutting mat from a craft store. Mark the cardboard with pencil or pen where you want to cut. Follow the lines with the utility knife. If you have a lot of cardboard to cut, change the blade as soon as it stops sliding smoothly. A utility knife also works for cutting apart boxes.
Scissors for Lightweight Projects
Scissors do a good job on all kinds of lightweight cardboard, including cereal boxes. They cut well in all directions and are handy for cutting all shapes, from simple squares and circles to paper dolls. Scissors tend to be the best choice for intricate cutting on light cardboard, such as when you want to make snowflakes. Kids and adults who are experienced with cutting shapes can often cut cardboard without a pattern. Alternatively, outline a pattern in pencil before cutting.
A hole punch works on light to medium cardboard, such as that used in gift boxes. Use a hole punch on cardboard for hanging ornaments or for holes to lace cardboard together for a book cover. An adult can use an awl or ice pick to make holes in heavier cardboard. A paper cutter with a lever, the type often used in schools, makes straight cuts in lightweight cardboard. A paper cutter is convenient for cutting cardboard in even sizes, such as for bookmarks, place cards or small signs. A craft knife with a pointed blade is a good choice for cutting curves and pointy shapes in cardboard.