For many years, I made good use of iTunes U free course resources. I watched the videos on my Mac using the iTunes client. iTunes U was available in the left top menu like below
At some point, it disappeared from iTunes and since then I have been watching (and even listening to) the videos on my iPhone using the iTunes U app. When at home, I have been able to view the videos on my television screen using my AppleTV. Not optimal, but it has got me through the day...
From time to time I have searched the Apple Store in hopes that iTunes U app has been made available also for my Mac since it was so much easier to follow courses directly on the Mac, but the message "This app is only available on App Store for iOS devices", meaning "Only available for iPhone" has always turned me down.
Now it turns out that the iTunes U courses never actually disappeared from iTunes in the first place. Even though the iTunes U option is no longer available in the top left menu of iTunes, the courses still are! They have only been moved.
To access the rich educational library, simply select Podcasts menu option in top left menu as below
Then, in the middle menu, select Store to access Apple Store. Now you can search for the topics you want to learn about. One of my favourite courses are covering the Swift programming language on Stanford university. When searching for the course it appears in the list. Fantastic!!
When clicking the Subscribe button, the course is listed in your Library section and you will then get new episodes as they become available, like ordinary Podcasts.
Hope this helps someone! I am at least happy to be able to follow along, coding and making notes, all using the same screen.