Here is a fantastic simulation game called Electrocity, that brings together many of the things you would have learnt about in the People's Planet topic. In this game, you try to grow a small village into a thriving city. But you will need to watch your energy management, pollution, and of course you will have to try and keep your citizens happy.
Here is a little screencast I have made that explains how it works.
After you have watched the screencast, go to: