Digital Publishing Suite will do that.
Whether it’s what you want or not is something only you can decide. There’s a dedicated forum: http://forums.adobe.com/community/dps
You can start by reading the FAQs and checking out the videos on Adobe TV.
"Targeting the iPad" is a kind of a misconception.
1. Create a PDF as usual (or perhaps downsample the graphics a bit to keep the file size down, as it's solely for viewing on-screen)
2. Make a regular HTML-based iBook document, ePub format.
3. Create a fully interactive DPS document.
For step #1: do Nothing. Optionally add a splash of color to pimp up title pages, headings, and tables. A big advantage will be the ePub version matches the printed version page for page (unless you go wild with redesigning the entire thing).
For step #2: do Everything. I don't think it's possible to do everything "just right" in InDesign to get a perfect iBook, you'll need to dive into HTML and CSS to get the most out of it. Even as such, the very best is still a bit underwhelming to my taste -- it seems the ePub format is designed to be just for novels, simple tables, and every now and then a grainy image. It takes a lot of effort to make it look Not Bad, which is still far from Good, and it's due to the inherited limitations of the format.
For step #3: re-do Everything and expect Nothing. The DPS format is great for interactive brochures -- see, for example, the U. of Dayton's app (http://itunes.apple.com/us/app/university-dayton-undergraduate/id450784479?mt=8). It looks great, has lots of interactivity but no highlight text or search button. Those options are not applicable to Adobe's DPS.
For school text books: well I dunno. Intuitively I'd say a straight-up PDF would do.