A prop, formally known as (theatrical) property, is an object used on stage or on screen by actors during a performance or screen production. In practical terms, a prop is considered to be anything movable or portable on a stage or a set, distinct from the actors, scenery, costumes, and electrical equipment.
Students are responsible for bringing their own props, costumes, puppets, etc.. for their films.
Releases are routinely used in film production, when they film, video or record the voice or performance of individuals, to be sure that the person consents or will not later object to the material being used for whatever purpose the release wishes.
For example, that the release wishes to use the images, sounds or any other rendering that is a result of the recording made of the releasor. This will help in ensuring the copyright owner has a clean chain of title.