JMoff,
While I agree with you in part, I do wish to clarify that I don't think any player should be using upcoming tests as excuses to miss team events. Part of the deal is for the player to learn how to manage himself, plan ahead, and handle multiple deadlines and requirements.
In my experience, those who learn to forgo FaceBook, TV, and texting as a sport, have no difficulty meeting all their commitments. If a kid got to the day before a test and had to miss practice to catch up on studying, if I were the high school coach I might well let that happen, but not without consequences. The player might be benched for a game as a lesson to both him and his teammates about what the expectations for them are.
College players should assume that they won't have even that option, and they should manage themselves with that in mind.