try this site: www.godonomics.com ....it has very interesting economic concepts taught in a fun way and at the same time teaches to be responsible economic systems.
in our school we often play an economic simulation game where groups of students are given various resources like scissors, paper & scale and asked to make perfect circles of certain measurement....however some groups are given lesser resources than others,,,,they are allowed to exchange their resources,,,,thus making them aware of international trade and the concept of developed & developing nations....its a fun way of learning important economic concepts.