A guided tour might seem like a no-brainer for a college orientation activity, but it is a critical method of helping students get to know the campus. Plan your tour route before the orientation, paying special attention to points of particular interest on campus, such as the various academic buildings, library and student union. Build time into the tour to pick up students' academic schedules if they haven't already received them, and allow them to try a dry run to find each of their classes; meet as a group after an allotted period to address any questions or concerns the students have after practicing.
A scavenger hunt is an entertaining way for students to get to know one another and the university campus. Compile a list of items ranging from easy to difficult in terms of acquisition, and then place students into small groups to embark on the hunt. Give students an allotted amount of time to find as many items as they can, and then have everyone regroup after the time period has expired. Give the winning group a small prize such as a gift certificate to the campus bookstore or to a popular nearby restaurant.
Typically, students will be divided into smaller groups based on things like the alphabet, living residence or intended path of academic study. Some of the students might already know one another, but for the most part the students probably will be meeting for the first time. Facilitate the meeting process by putting everyone at ease with an icebreaker activity. These activities tend to be a bit silly to loosen everyone's nerves, so choose something that will work for the size of your group. You could play a game, or you could go around in a circle and name an interesting thing about each person, depending on what you feel will be most effective.
Some dining halls are better than others in terms of culinary offerings, but it can be strange for students to transition to college dining from home-cooked meals. Take the students to the dining hall for a quick tour of the facilities, and then for a fun activity, offer lessons on how to make their own culinary creations right there. Older students often have favorite things to make based on the ingredients that are available; depending on what you have to work with, show the students how to make easy items such as pizza bagels.