The most obvious thing is your rent. The cost for the internship program is $180 for the first month, and $150 each for the second and third month ($480 for a three-month stay).
Another important thing to consider is travelling costs. These obviously vary for almost everyone as we have had people here from as close as Indianapolis to as far away as Germany!
Generally, interns spend around $20 - $30 a week on groceries. This again depends on each person. It is possible to spend less than this if you need to.
"Ethnic Night" occurs every week. The staff and interns get together and go out for a meal of a different ethnicity each time. It is completely optional so if you need to save money you don't have to go but it is also a lot of fun and a good way to get a change of scenery. Usually, the places that are chosen have reasonably priced food so it's not always expensive.
When you arrive you are given a staff t-shirt. Interns usually buy at least one more t-shirt and other "Staff" items like sweat-shirts and long sleeved t-shirts. Again this is optional.
You are likely to want to spend some of your free evenings away from the park to get bit of a break so it is good to take into account possible trips to cinemas, restaurants, the Mall or the Battlefield Museum.
Many an intern has encountered the danger that is the Wolf Park gift shop. It has many goodies to offer and few have managed to escape without spending anything. Be prepared to spend a large amount of money there. Either that or have very strong will power!