Natural Math is a web mathematics community for math teachers and students founded by Dr. Maria Droujkova. Despite being in is beta state, it’s one of finest math community website I’ve seen so far. It has a variety of features: a blog, a forum, a group interest and many more. Some of its notable projects are Math 2.0 Group Interest, Math Lexicon and Special Snowflake.
The most current addition to Natural Math, which is one of my favorites, is the Ask Natural Math page, where community members can ask, answer questions as well as edit and improve them. The text below is the general description of Ask Natural Math taken from its About page.
Here you can ask and answer questions, comment and vote for the questions of others and their answers. You can revise and improve all questions and answers. Questions can be tagged with the relevant keywords to simplify and organize them.
This site is moderated by its members, hopefully – including yourself! Moderation rights are gradually assigned to the site users based on the accumulated “karma” points. These points are added to the users account when others vote for his/her questions or answers. These points (very) roughly reflect the level of trust of the Natural Math community.
No points are necessary to ask or answer the questions – that’s where you start!
It is important to note though, the since it is a math community for with variety of users, users who answer questions should consider answers which can be easily understood by all readers.
Visit Making paraboloids and such for little kids to see a sample discussions of Ask Natural Math.