@NewChessDad:
The whole Puzzle Rush is only a couple of months old, but my question is whether there has always been an unrated version (Learning) or they just slipped it in recently. Thanks for the reply though.
As to seeing the games the puzzles are from...Pretty sure the Chess.com explanation would be that they are trying to teach pattern recognition. I seem to remember that in at least some of the strategy courses (Lessons-formerly the Chess Mentor) a link is provided.
Or have I just been gloriously unaware? Oh wait, it's not necessarily an either/or question...sigh.