Card Game: AP Stat Ideas

Below are 4 hands from the game "13" that my students now play all the time now that projects are getting finished and school is ending.  Apparently 2's are the best.  I don't know the rules, and I'm not certain they do either.  I believe you can play straights, multiple pairs of multiple numbers, I don't even know.  Do people besides students at my school play this game(i.e. do you know what a "cutup" is)?  An interesting way to analyze probability anyhow.  Here are 4 real hands dealt during a resource period.  Ideas...who will win?  who has the "best" hand