It has thousands of free Ebooks that students can read, and it also lets them easily annotate them — without requiring any downloads. Most of the books don’t seem to have an audio option, but it still has a nice collection of those that do. Of course, books with audio narration are ideal for English Language Learners.
Teachers can create virtual classrooms though, as Richard notes, the process is a little time-intensive. It would be nice if they didn’t require as much information on each students as they do in order for a teacher to add a student to their classroom. Even better, it would be great if they allowed students to just use a code given to them by their teacher so they can sign-up for themselves (other similar sites have that feature).
But they are new, so I assume they’ll be making those kinds of changes over time. Their selection of books really stands-out right now, and their annotation process is easy-as-pie, so it’s really worth looking into it despite my minor complaints.