i knew a girl from my old home mountain that could 7 30s and 40s... she was getting switch 5s down last time i saw her too...that was last season tho... i think she was only like 16 too. not bad
there shouldnt be such thing as "good for a girl". Skiing doesn't involve huge amounts of strength, so there is nothing preventing girls from being as good as guys.
parks obviously not very hard if theres ten year olds out there killing it. It takes what? 2-3 years of pushing it to be considered "really good"? I mean you seriously don't even have to turn. Just ski up to a jump pop and drop a shoulder and all of a sudden you are a good skier? It's a joke.