Final answer:
OpenStax books are available for free to students from On The Hub.
Step-by-step explanation:
The software product that is available for free to students from On The Hub is the OpenStax books. OpenStax partners with the Institute for the Study of Knowledge Management in Education (ISKME) to offer Community Hubs on OER Commons, where instructors can share community-created resources that support OpenStax books, free of charge. These resources include additional ancillaries, teaching materials, multimedia, and relevant course content.