What ebook format are you talking about?
It could be interactive PDF, EPUB (reflowable or fixed layout), SWF, Publish Online.
it's a fixed layout ePub
Moving to the InDesign EPUB forum.
I would suggest is an MSO over the entire page with the first state of the MSO holding a fill: none/stroke: none object (null).
The information you want them to see would be in each object state.
Then button actions would be set to show each state.
When the viewer clicks a button, that MSO state would fill the page. They could only see that MSO state if they clicked the button.
One button for each state.
Finally, you will probably want a "Reset" button to go back to the original page with the empty state.
It will be a problem if the hidden information is too long to fit in each state on only one page. But you can have as many MSO states as you want and as many buttons.
It's a perfect use for MSOs.
I have a new book on animations that actually covers this topic. You'll find it at Amazon or Adobe Press. (No link given.)
And one more thing.
This technique can be used with Interactive PDF using the Show/Hide Field actions for button.