Won't be given in Italy.
That is what I have learned, in this, my third part of travel stuff.
I'm pretty sure that this isn't entirely true. But it is true at least if you go to more famous things.
I suspect that this is true in most cases for more famous things. In Paris, which isn't in Italy, you won't get a discount when you go to the Louvre. I don't know why, I mean it isn't like they get millions of people going there each year to see things, but you don't.
You do at the Catacombs, and at Invalides though.
The Rembranthuis has a discount of about €2.80 for students which is good, compared to €1.50 at the Catacombs and €2 at Invalides.
However, I don't remember getting one at the Deutsches Schiffahrtsmuseum. And to be honest the saving at Neuschwanstein was €1, which incidentally was the same saving as in Walhalla.
Italy however seems to work on EU citizenship. I may be living in Australia but I am technically a citizen of the EU under article 17 (1) of the Treaty of Rome. I didn't have to prove it in Rome and the Necropolis at Tarquinia (something I should write on), but I did in Florence, so I paid the full price because the consulate for the relevant country of which I am a citizen of (as well as Australia) didn't have a fingerprint machine and I couldn't be bothered paying $100 for a temporary one to save about $30.
The student discounts are ok, but I've found that you don't need to get an International Student card thingy. Places didn't accept them, and other places, like Walhalla for example, were happy enough to accept a student ID from the university.
However, the discounts don't seem to work for students over 26. Invalides, the Vatican Museum and a bunch of other places have an upper age limit of 26. The places in Germany didn't do such a thing which was good. I saw this limit annoy one man at the ticket counter in the Vatican for that reason. I didn't have to worry.