Need something to distract the kids while they're waiting to head out Trick-or-Treating? You could have them try out a Creepy Computer Game in R! Engineer and social scientist Dr Peter Provost translated one of the old BASIC games from the classic book Creepy Computer Games into R: just have them type in this file (and yes, they do need to type it character-by-character to get the full experience) and then source it into R to play the game. The goal is to move your character
* to the exit at the SE corner of the graveyard populated by gravestones
+ while avoiding the skeletons
For extra credit, see if they can figure out the bug that causes the move counter to go down, instead of up. It might help to refer to the orginal BASIC sources — the book is online at the publisher's website as a PDF here.
The Lucid Manager: Celebrate Halloween with Creepy Computer Games in R