Help with creating interactive presentations on Mac



I'm pretty new to this, so please forgive me if I am asking stupid questions

I'm beginning a new job as a teacher. I'm very used to writing presentations in Keynote and also using LaTeX Beamer but I want to write some with a much greater level of interactivity for my soon to be students.

A Powerpoint example of the type of thing I'm talking about can be found here

The second page has animations and also an interactive drag and drop questions bit.

I was thinking about learning Flash but then found out that it isn't possible to run Flash in Keynote anymore. I could write some bits in Keynote and some bits in Flash but this seems a bit daft to me.

I was wondering if any of you very experienced people out there could help me. If you wanted to write presentations which could do this type of thing in a single application on your Mac, what, if anything, would you use?