There are two things that you can do with your money, you can buy things or do things. Rather, ask how you take advantage of the opportunities the trip offers you and how you allocate the funds you have at your disposal. The dollar can fluctuate sharply. Many students buy currency ahead of time when they judge the rate to be favorable. You can buy travelers checks in Pounds Sterling or Deutsche Mark in some places.
Work study is the exception and side jobs are practically non-existent.
In some countries students can do well teaching English to eager learners. Before you go keep a short record of your expenses here. If you require a special diet, you need to bring supplementary funds. A weekend in Venice, an Irish adventure, a climb in the Alps. Best to ask past travelers how much they spent.