You can take your course content and create an ePub (an eBook) and share it with your students. You can email the ePub file you create to students and they can open it in the iBooks app on their iPad.
ePubs give students more flexibility in terms of readability (they can adjust the text size, font, and screen orientation). ePubs also have iBooks features (ability to set bookmarks and add notes, a dictionary, and a table of contents for easy navigation). And an ePub allows you to incorporate photos, videos, links, and audio into your eBook.
Creating ePubs with the Pages Application
Pages is a word processing and layout application that can be used to create ePubs.
To create an ePub, either open a Word document in Pages or create an original Pages document and simply export it as an ePub. Then email the ePub file to your students as an attachment. When they open the file using the email app on their iPad, they are given the option to open the attachment in iBooks.
ePub vs PDF
Some students will likely prefer one format over the other, so ideally you will want to offer materials in both ePub and PDF formats.
The same copyright policies apply to ePubs as any other course materials.