I can't recall what I did to get these apps onto my screens, but my iTunes app shows purely music. The AppStore icon gets me to both apps to purchase and apps I have downloaded. The iTunes U app I remember downloading through the AppStore icon and has downloads for educational material. So to answer your question, the "iTunes store" on my iPad is the icon "AppStore". I hope that is not confusing, and I doubt you are any older than me.
Regards, Andrew
Let's just say that when I was born, the Dead Sea was still just "critical".................
...and many thanks for the answer - I'm sure I will sort it out.