Well I sometimes have curious ideas but I've always wanted to develop a one year project based on the following idea: pupils must create a country.

It can be a long time project or even a shorter one. However, the idea is to create the most realistic country. I think it's possible to represent it like in google earth. You can create its shape and boundaries. The following site gives ideas to create one with Google Earth: http://sites.google.com/site/geinvtclassrooms/Home/create-a-country

Then, it could be interesting to imagine the people living in the country. Pupils could compose a national anthem, imagine a flag, rules, etc. All these elements could be the subject of various lessons.