There are many ways you can build a medieval castle. But first, prepare the materials you will need. These are empty cereal boxes, white glue, paper towel tubes (or tissue roll tubes), scissors, and masking tape. Using your imagination or a picture of a medieval castle, arrange these elements to form your castle. You can paint the cereal boxes, but water could make it too soft, or you could cover it with colored paper. Use the glue sparingly as it would make the cardboard soft. The paper towel tubes can be used for the tower. Cereal box top covers may be used as the roof of these towers.