A diorama of a biome is a miniature landscape that shows the different types of animals and plants that live in that region. To create a diorama for a deciduous forest, begin by forming the physical landscape. Once you've laid out any rivers, lakes, hills and mountains, you can add the trees and animals that live in the biome.
Paint Your Box
Take a shoebox or another large box, remove the lid and lay it on its side. If two of a box's sides are shorter than the others, these should be oriented vertically.
Paint the top side of the box's interior blue to represent the sky. Paint the three vertical interior sides of the box blue for the sky as well; you can also paint mountains or hills at the base of these sides to show the distant landscape of the forest. Finally, paint and texture the bottom of the box. A deciduous forest has many rivers and lakes, so you may want to paint a blue lake or river on the bottom of your diorama. Use a different shade of blue from the one you used for the sky. Paint any ground in your diorama green for grass or brown for dirt. You can also texture the ground by gluing dirt, pine needles or small pieces of leaves to it.
The deciduous forest covers some of the most populated regions of the Earth and includes a wide variety of terrain. Flatlands, swamps, rivers, hills and low mountains can all be found in this biome. If you want to include hills or mountains in your diorama, try modeling them from upholstery foam. For low hills, simply cut the foam in the shape you want using a craft knife or large steak knife. For larger hills or mountains, cut several small sheets of foam, layer them on top of each other and glue them together. Glue your hills to the bottom of your diorama and paint or texture them as desired.
Trees and Shrubs
Once you've modeled any hills in your diorama, begin to place vegetation -- trees, shrubs and flowers. You are modeling a forest, so trees are an important part of your diorama. Most trees in the deciduous forest are leafy, such as maples, oaks and birches, though you can include a few coniferous trees such as pines. You can buy model trees from miniatures catalogs, or make your own using small twigs as trunks. Smaller bushes, found on the forest floor, can be modeled using smaller twigs. Attach your vegetation to the base of your diorama using superglue, and hold them in place until the glue has dried. If you created hills, you can press the base of your trees directly into the foam.
Include Local Wildlife
The deciduous forest is home to a wide variety of animal species, including deer, rabbits and bears. Because a diorama displays all the species in a biome, you should include these animals as well. See if you can find a single set of model animals that includes the animals you're looking for, as this will ensure that all animals in your diorama are to the same scale. You can also create your own animal models out of modeling clay. Place your animals in your landscape to show their typical behavior -- for instance, a squirrel climbing a tree or a frog at the side of a lake.