With the ubiquitous iPad replacing the old-fashioned pen and paper, students are going to need easy and simple resources for note-taking on touch-screen devices. Enter this great post from Free Technology for Teachers: 5 Free iPad Apps Students Can Use to Take Notes. Check out the website for complete descriptions of each app, or download the apps and see which one best fits your needs.
Penultimate provides a place for you to hand-write notes on your iPad.
inClass is a fantastic free iPad app that students can use to take and keep track of the notes they record in all of their courses.
Evernote is the Swiss Army knife of iPad apps.
Fetchnotes is a service for creating and organizing notes for yourself.
Last but not least is Google Drive for iPad.