In addition to discontinuing iBooks Author, Apple is also discontinuing iTunes U by the end of 2021, announced in a support page.
Canceled: iTunes U
In 2018 Apple released new tools to help educators: Classroom, Schoolwork, and Apple School Manager. Other Apple apps with education features include Pages, Numbers, Keynote, GarageBand, iMovie, Clips, and Swift Playgrounds.
In addition to Classroom and Schoolwork, Apple also introduced Apple School Manager to enable IT Administrators to easily manage iPads, Macs, Apple TV, Apple IDs, books, and apps, while ensuring data is kept secure and private. Apps such as Pages, Numbers, Keynote, GarageBand, iMovie, Clips, and Swift Playgrounds have education-specific features that are used regularly by teachers and students.
On the publishing side, Apple recommends using Schoolwork by adding support for ClassKit within iTunes U. Apple is also adding an export feature to iTunes U to support moving to 3rd-party apps or Learning Management Systems.