You can get useful answers from here but most of the time you have to wade through a lot of garbage, joke answers, and general stupidity. It's good for answers to small questions but I wouldn't let kids on there. They could end up accidentally clicking the wrong link and seeing stuff they may not understand.
There has been many a time where this site literally saved me money, time, and let me keep my peace of mind. There have been times also, when I found this site to be less than helpful. Use common sense and plenty of logic, and this site can be a real help!
The main problem I have noticed is that in the political and religious based questions, the answer that gets voted the best answer is usually the answer that the asker wanted to hear, rather than the most correct answer.
Just ask any question and your guaranteed to get an answer. Just use caution when using this site though because anybody can post anything. Someone even asked for my credit card info and said he would buy something for me! Sure he would.