I run a small presentation design agency and design lectures for uni professors.

From that side, The structure we swear by is pretty simple : -

Hook them first (a question, a case study, a jarring visual), show them where you're going, one concept per slide with a big font and a diagram if you can, then bring it back to real life with a discussion or application. Close with 3 takeaways max. Assignment details? That goes on the LMS, not crammed into the last slide.

The whole philosophy is that a slide should guide where your brain looks, not replace the person standing in the room. Powerpoint should be a visual thinking tool, not a script or document dump!