We don't have our own, but my daughter's class incubated and raised ducklings when she was in third grade and we had them home to stay with us over the weekend a few times:
Yellow one was named "Coin-coin" ("quack-quack" in French--my kids are in French-immersion school) and the darker one was named "Petite-brun" (little brown). There was a third who hatched, but didn't make it that the class named "Chocolate".