The film arts relates to all aspects of the production of film (television or movies). The course in the film arts would require students to study everything that goes into the making of a film. The following are a few specific aspects of film art: story, setting, camera work, lighting, sound, sound effects, costume, hair/make-up, special effects, animation, editing, music/score, crew etc. Each of these areas is a specialty that requires specific training. If you think about the multiple names that appear in the credits of a movie or television program you come to realize what a multi-faceted production it is to create a film. There are literally hundreds of people involved in all of the various elements of what becomes the finished product.
A study of film arts would also be likely to include a study of various types of film and what specific requirements those types of films require. Animation is very different from fictional drama. Documentary is very different from fiction. Each type of film requires a different approach, but there is also a common ground in film, and many of the aspects listed above would be necessary to a production of any kind of visual media.
The creation of a finished film is the combined work of many "artists" who contribute their talent to an aspect of the finished product, and that finished product can be as much a piece of art as a painting or piece of music.