like this one. Now, thanks to Ken Halla and his US History Teachers Blog I have another resource to use.
The Eli Whitney Museum website has an animated illustration of the cotton gin and how it functions. You still might have to explain some parts of the process and you will still have to explain to students why the cotton gin is significant in US History, but the illustration is still helpful.
Applications for Education
You might want to pair your use of the animated cotton gin with this primary source lesson plan from the National Archives. The lesson plan is built around the documents and drawing that Eli Whitney submitted with his patent application.