I'm a high school teacher, and I had a rule for a while whenever students wanted to make powerpoint presentations. They had to build on-screen navigation into their presentation, just as if they were building a website. When they were giving their presentation, they had to use the on-screen navigation, instead of clicking forward and back. The navigation had to be semantic, it couldn't be just "next" and "previous".
Presentations were interesting, because people were free to interrupt with questions such as, "Your data seemed to show xyz, can you explain how your conclusion of abc really follows from your data?" Then students could click right over to the data part of their presentation, without flipping through all the slides in between.
Like most things, the problem is how a tool is used, not the tool itself.