The Giver by Lois Lowry

You can't see color. You don't really know love, but you don't know pain either. No war or peace either. Pointless rules are made. This is what Jonas discovers, when at the age of 12, he is assigned the job of The Receiver. The Receiver collects the memories about the past (a.k.a. where we live now and the past). Some memories are happy, invigorating ones like riding a sled on a fresh, crisp, snowy hill. Other are hard, painful ones like seeing the destruction of war. Over time, Jonas discovers that the "utopia" he is living in is really a dystopia, and one memory can change your life forever.