How do I calm wolves in Minecraft?

You can choose to kill them if you have the skill and ability to deal with 13 suicidal wolves. Or, you can die to them once and once you leave the game and come back, the wolves will no longer be hostile towards you (Source: my testing in a singleplayer 1.8.8 world). Another way is to simply leave and re-enter the world (thank you, Ben) and the wolves will no longer be hostile towards you. Else, you cannot calm angry wolves directly.

I made a 2 large and 1 long with 4-5 blocks profound. I pushed the angry wolf there, then poured a lava bucket on the top of it, waited a sec.. Then felt bad, then it was dead without alarming the others. (n_n)/