Here's a sponsor family's view of "what plebes do on Saturdays during ac year." After having coordinated pick-up sked via email on Thursday and Friday, we do a drive-by at the Mid Store around noon or whenever the plebes get released. Lots of last-minute jockeying as plebes fail to come up to scratch in company and don't get cut loose until they get done what they were supposed to do, maybe 3 hours later. Some days we might make 3 pick-up trips, especially if varsity athletes have practice or a meet.
Maybe drop them at the mall for a movie, go pick up later to bring back to house for dinner. Usually, it's straight to the house and change into "reg P.E. gear," of which we have drawerfuls passed down by previous members of the sponsor family. Kind of fun to wear vintage '98 blue rim T-shirt. Then, it's right to the designated snack cabinets and refrigerator for food, EZ mac, ice cream, etc., then down to the TV room for movies...but within 30 minutes after eating, we'll have a handful of plebes face down on the sofas, napping for 3 hours straight. For the extroverts, it's a chance to re-charge with swapping stories with sponsor brothers and sisters, watch movies, play with the 3 dogs, hit the pool, relax with no one yelling. For the introverts, it's a chance to go elsewhere in the house to be blessedly alone and gather their thoughts.
It's usually dinner for 10-12 at our table on Saturday night, a mix of plebes and upperclass brothers and sisters who mentor them with humor and patience, observing wardroom etiquette within the sponsor family. Youngsters dish the ice cream while the 1/C and 2/C direct leftovers stowage and loading dishwasher. Plebes are excused with their bowls of ice cream to enjoy the few hours of liberty left. Presto change-o, back into the uni of the day, and they get hauled back to Mother B in plenty of time to check-in.
Many plebes haul books and work over to do on Saturday, but end up falling asleep or mentally checking out. The rhythm they usually fall into is maybe bringing just 1 problem set to do, the 200 pages they have to read, or the 5 page paper to outline, on Saturday. Sundays are usually the days most plebes devote to getting organized for the week (academics, pro quizzes, uniforms, room titivation).
Note, all of the above occurs on Saturdays when a plebe has town liberty. There's plenty of duty weekends and "mandatory fun" when liberty is either non-existent or minimal.