I made that complaint--as a flippant remark in class--to a high school statistics teacher once so he assigned me the task of writing my own final exam rather than taking a final exam, and gave everybody else the option of taking my exam or his. (Nobody took mine.)

My grades weren't that great (classic B student) and I doubt I had better mastery of the material than the more studious ones in class. But writing the exam was both fun and challenging--I definitely had improved mastery afterward, as well as a newfound appreciation for his job. He gave me a B+, though, out of fairness as I had several days to write the exam, open book. Which was fine by me.