"All that we call human history--money, poverty, ambition, war, prostitution, classes, empires, slavery-- is the long terrible story of man trying to find something other than God which will make him happy." -c.s. lewis
...and it never works. Other things can make us pleasure for awhile. I don't think it is a bad thing enjoy those small pleasures - like a good grade or a cute boy or a delicious meal. In fact, we should look for happiness in everything - But, at some point your grades will not be what you would like them, that boy won't be interested, and dinner won't taste so good - when this happens, you should not be miserable in the slightest..... because your happiness is grounded in something deeper, something stronger. The beautiful thing, is that the deeper and stronger thing isn't flippant like people, it is constant - unchanging - reliable. It is Love. It is Him.
"God can't give us peace and happiness apart from Himself because there is no such thing."-c.s. lewis