Depending on the size of the high school, it may be very easy to know who's doing what and judge people based on the cliques they are in. Because of this, it seems like there's more pressure to "fit in" with a group when a large portion are partying. College offers a wider range of groups to join, many of which do not enjoy the party scene. At a large college or university it may be easier to avoid the pressure to party and "fit in" because not everyone knows who you are and what you're doing. There are also lots of clubs and other activities to be part of - one Iowa college has 700 clubs!
In high school, some students may expect other students to party. College isn't that way. Many college students respect others that choose not to be out partying every weekend.
