We meet three days per week with students and two days without. It gives the mentor-folk a chance to plan things out, organize tasks for our students to accomplish, and take care of some of he boring work that students can't participate in such as milling.
Since last weekend, we've left the lab on most days no earlier than midnight. Once I go out tonight, I'm not planning on being home again until Sunday. It's better not to raise my expectations too high by thinking of things as exotic as food or sleep or a social life.
I'm sure most of the kids will be there right along side me, but because we meet so far away from many of their homes -- 20+ miles for some folks and completely unable to get home without team transportation -- a lot of parents force their kids home early.