Interactive 3D models

So I had an Idea of having 2D image targets ad displaying 3D models to create an educational app. After receiving feedback on this idea I need to add some interactivity to this application. My HOPES are to expand on this idea by having the virtual 3D models interactive, in which I mean if you tap the 3D model it will display a specified animation or display a message. I know about virtual buttons but I want the virtual 3D model itself to be interactive. Any ideas...
Your help would be so helpful it's unbelievable how much I would appreciate it.