An ATM machine is located near Bernardi, and many ATMs are located throughout Rome. One of the best ways to deal with money is to use your cash card to withdraw money instead of using your VISA card, especially given the current euro-to-dollar exchange rate. For example, if the currency exchange rate is €1.00= $1.41 and you buy something with your credit card that costs €15, keep in mind that when you receive your credit card statement, it will probably show $21+ due to the day's (September 6, 2011) currency exchange rate. In addition, be sure you check with your bank about the amount of money you are able to withdraw at one time and how much ATM fess abroad will be. Let your bank know that you will be overseas for a period of time.
Often, students are very resourceful, and they find inexpensive hostels, restaurants, etc., online when they make their travel plans, so it is really up to each person's personal budget and how good the student is with budget management. (Thanos can help/advise students individually on this.) It is probably best to budget at least 120 Euros per week for meals.
The Euro is worth more than the dollar and it adds up over the course of the semester, so be sure to check your bank account frequently.