The major change between my high school day (graduating in 1986) and today in terms of what students do in their free time has to do with technology. Technological changes have made it so that students are more likely to do things on their own than they were in the ‘80s.
Today’s students have more technological options available to them as forms of entertainment. In particular, they have more things that they can simply do at home. Most things that students did in the ‘80s for fun had to be done outside the house. Students in those days would typically do more things in public and with groups of other students. Today, students are more able to stay home by themselves in their free time and use technology to entertain themselves.
I agree that the major difference in the way students spend their time now has to do with available technology. Technology allows student to be both connected and disconnected from the world. They can connect by participating in discussions and obtaining news from across the globe. They can be disconnected by spending time on screens and not in their own community (outside in the neighborhood, sports, programs, etc.) I think technology has also led to less "face time" with others. Students have less interaction outside of the classroom because they are more easily able to entertain themselves with technology without the aid of others.