A bad word...

Jackson used his first "bad word" this week. He has taken to saying "Darn It!" when something isn't going his way. It's happened three times now, and he uses it in context. This isn't a great word to use and we discussed that it isn't something we want our 2.5 year old to say but what is a better option?? Shucks? Bummer? I'm not sure there is a better option and darn it is sure better than what I tend to say when things don't go my way.