Depends on what you think is appropriate for kids. Its a personal opinion Pink! cusses and Lady Gaga is a freak show but both are good artist and you can't hide the bad stuff from kids for long or they will learn to resent what you deem as good.
I think it is safe for teens, for kids, just make sure you check the song before they listen to it because some have swearing and sex references, although in my opinion it is just music so whats the bother? but just make sure if you buy it of itunes get the sensored versions cos they won't have swearing
I didn't much care for the scanty undies and the very high heeled shoes whose heels looked like men';s sexual organs-THAT was pretty gross & I've seen a lot! I wouldn't have wanted anyone under 13 to have seen that......its a shame she has to hide her looks & talent behind such tacky costumes.