Your role is crucial.
We can provide the training, but to change the culture so that no one ever suffers through another 'death by PowerPoint' presentation, we suggest that you meet with your participants before and after our time with them. Make it one-on-one if possible.
PowerPoint is a brilliant visual aid, but only when it is used correctly.
Traditional use of PowerPoint stifles discussion and critical thinking, and dulls focus. It's boring. Slide after slide switches audiences off, steadily reducing their ability to take in information. You are wasting your time - and theirs.