Dioramas are three-dimensional models, usually done in miniature scale, and built to recreate specific moments from history or fiction. They are often used in schools for simple class projects. At Greendale, the Anthropology class had many such diorama assignments. However there were a few exceptions which were created specifically to promote a cause, recreate a scene from a movie and plan an elaborate heist. They first appeared in the Season Two episode "The Psychology of Letting Go".
This is a diorama Annie built for the annual "Green Week" event held at Greendale. It features a miniature electric car going from the "dark" era of fossil fuels to the "bright" era of alternative energies.
This diorama was constructed by Greendale's Glee club conductor Cory Radison. He had planned the stage direction for the upcoming Christmas pageant down to the last detail. Abed noticed he had Britta in a non-singing role as a tree.
This diorama was constructed by Jeff. He and the study group were using it to plan an elaborate heist to infiltrate the school and rescue Dean Pelton who was being held captive by Ben Chang. Shirley disliked the fact that Jeff made a working miniature water fountain but used a pine cone to represent her.