Copyright and Fair Use LR

Number twenty of the quiz was the most surprising to me. If a school creates their own cd using all fair use material, I don't see why they wouldn't be able to copy and distribute/sell it. The quiz says that it would be allowed if there was no anticipation of "wider distribution." That makes me wondering what the criterion would be for the word 'wider'. Maybe 10, 20 or 100 people? I think that laws and rules like this would and could be more easily followed by educators, or just anyone, if they were more common sense and with fewer variations. It's sad that we can't all just share our video, audio and graphics with anyone who wanted them, no matter if you're an educator or not. Bottom line, is that if you make your own product legally, you should be able to sell it if you want. I just don't understand how it could be any other way than that.