First, I think this is quite a thought-provoking post, and ehdonhon, cjf, and MeowChow, make valid points above (which I would lessen by repeating).

Part of the difference between the two scenarios is that an assignment such as in scenario 2 is almost always designed to give the two children an almost real-world way to test what they have learned. It has been my experience that until one reaches collegiate-level programming classes, team programming is a rarity.

In scenario 1, however, it is most likely that the two programmers were not given the task as, "learn how to do X by Tuesday, and you'll get your grade on Wednesday," but more often, "can you find a way we can do X," where a solution will be evaluated based on how well it does the job, licensing issues, and benefits vs. work involved for installation and maintenance (besides which, "use no modules" would likely NOT be so much a requirement as limiting system downtimes and disruptions).