I have worked with about ten great undergrads this year in mentored research.

I invited them to have an end-of-year party at my house this evening. I haven't hosted a party in, literally, 15 years. They like drinking so I bought some... beer? and hard lemonade? I chose by label color. People like chips and dip, right? And hot dogs?

http://s2.quickmeme.com/img/0a/0a3d2a086eaafe832d58281eeab1858cd3bd3e3d4736e582a383b3aee933a14c.jpg

@tomstearns If you're looking for a serious answer, I'd also get some non-fizzy and/or nonalcoholic drinks (very likely someone will really appreciate apple juice), a fruit plate, and one of those two-pound bags of M&Ms. Also make sure you ask about and accommodate any allergies or other dietary restrictions (other including vegetarian/vegan/kosher/halal), or it's not much of a party for those who can't partake.