Most of the Stanford experience revolves around on-campus activities. On any given weekend, there are many popular parties on campus, especially in Greek houses. There are also many house parties and/or progressives. Many Stanford students hang out with their small groups of friends on Saturdays and Sundays before going out to major parties.
Students are usually satisfied with the campus nightlife, and when it gets old, students go into the city, on occasion, to experience a new atmosphere. It is true that Stanford's spring quarter is the best quarter for nightlife and parties. There is something to do almost every day of the week, and it always involves something exciting and fun.