My wife and I had 4 good nights here. We wanted clean, simple accommodation at a budget price and got exactly that. It is run by nuns and contains a primary school, although the children were on holiday. Being an ex teacher I would have liked to see it up and running. Will have to go back.
It is a large, rambling old building with a central hall and court yards; pretty much what you'd expect in Venice. The rooms are clustered together at the back on the upper floors; third and fourth, I think. There is a lift though. We looked out onto more old buildings which seemed to be flats for native Venetians. The main door is impressive but set back from the hustle and bustle of one of the main walking routes between Rialto Bridge and St Mark's Square. These two sites are about 5 minutes stroll so you are very central. The institute is right on a busy little canal. Plush gondolas, food-supply boats, police, the bin men, all sail past. So it's busy, interesting and atmospheric. The accommodation itself is calm and quiet though, as you'd expect in a religious building.
The room was simple but comfortable. There was an efficient air conditioning unit for which we were grateful. The bathroom was fine. The nuns are courteous and helpful and require you to be in by 11 pm. They speak decent English and they listened patiently to my rudimentary Italian and even taught me some new vocab.
We paid 74 Euros per night for our double room. There was no breakfast but there is a small dining room with a fridge and microwave where you can rustle up your own breakfast. There is a small, well stocked supermarket 1 min walk away. Also every kind of cafe and restaurant within a stroll.
We booked it through Monastery Stays, who have a useful web site of similar accommodation throughout Italy. Their charge is hefty though, a further 74 Euros, which only becomes apparent at the end of the booking process. They only point out that they take nothing from the accommodation providers. If I were to book again I would ring the Institute directly.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC