A solution came after reaching out to my colleagues in the world of Twitter. Wes Fryer and Kevin Hodgson both came to the rescue by offering helpful advice (thanks guys!). A free SAM Animation download was the first option... I downloaded the software and the experiments began! The next software suggestion was JellyCam Stop-Motion Maker but unfortunately my Mac is a bit too old for the latest version so I will be looking for other ways to use the program.
Kevin's "Making Stopmotion Movies" site has been extremely helpful by offering steps, planning sheets and handy tips. The students and I refer to his site again and again!