Like all work done in school, the final product should NOT be the end all and be all, but it is the process that is important. So, in designing your course you must first have certain "gates" the students pass through before they turn in the final image. For example they must be able to understand and show the use of the elements and principles of design in various steps through different photo shoots. So it would be harder for them to steal images if you require a sequencing of images or "bracketing", as usually stolen images are "one ups".
> Next year I'm switching my photo curriculum from darkroom to digital.
> How do digital photo teachers know your students actually took the
> photos they turn in for projects? With all the online image
> resources out there, how will I be able to determine what is actually
> my students' work?