This is a great resource ...
I'm pretty sure that people will come and have a look and maybe even use the materials to learn something. The next step is to refine and polish the materials a little and then to ask a few of your friends to take a look and see if they have any suggestions to help you improve the resource.
Yeah -- wiki's are amazing.
Not sure if you tried this yet -- but on the left hand side of the screen there is a link called download as pdf. This will automatically generate a print version of your materials - so kids you don't have access to the internet can get a print copy. In fact you could develop a book on the planets if you wanted to.
I look forward to seeing the next draft.