PD_CommunicationAndCoordination TCPP_Programming K_12 CS0 DSA Systems visual

Oklahoma Supercomputing Center for Educaton and Research (OSCER)

“Supercomputing in Plain English” - Shared Memory, Slides 103-104.

After the first game (Take the Pen), students are asked “Can the outcome be predicted in advance?” They are led to the answer “no”, and to understand this is situation represents a race condition (Neeman2006).

The question is repeated after the second game (Look at the Pen). Here, students are led to the answer “yes”. Through the game, they come to understand that race conditions occur on writes (taking the pen) rather than reads (looking at the pen). (Neeman2006).

CS2013 Knowledge Unit Coverage

Communication and Coordination

2. Give an example of an ordering of accesses among concurrent activities (e.g., program with a data race) that is not sequentially consistent. [Familiarity]

TCPP Topics Coverage

Programming Topics


This game may be difficult for blind students. For students who are deaf, instead of saying the word “go”, the instructor could offer a visual cue (e.g. thumbs up) instead.


Unknown. (Neeman2006) describes the different analogies. There is no assessment provided in (Neeman2006) or (Neeman2008).