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There are many new social interactions in The Sims 2: University, including Pranks, Instruments, and Pillow fights. University adds several categories of interactions, including "Influence To..." and "Hang Out". Sims can comprise Study Groups, providing social interaction while boosting grades. A common interaction between University Sims is "Kicky Bag", a hacky sack knock-off in which multiple Sims try to keep aloft a small bag filled with beans by kicking it to each other. Young adults can also streak on the University area.