This is a tricky one, because their meanings are very similar. These two dictionary entries give several good examples of uses.
Now that I've read them I can't think of many different examples. Classical is used to refer to specific things like music, dance, or civilization. Classic can mean the same, but often carries with it a value judgement that something classic is desired or good. Something that is classic is something that has lasted a long time and is likely to continue to.