Since we need to give our customer bitcoin as reward when they pass exam, we are willing to buy some bitcoin from market. You can register in our site, buy amazon gift card with BTC at:
http://www.wise168.com/shop/index.php?main_page=product_info&cPath=22&products_id=30Running a bitcoin exchange market is not our purpose, so we do not provide live price, we will rather buy small volume at higher prices. (20% higher than live market). BTC requested will change every 8 hours, and remain stable during that 8 hours. It's up to you to decide when to sell.
Note, however, that the goods is available when we need bitcoin. That is, when customer get coupon and order BTC from our shop. We also encourage our new friend to take part in our game, and get some kind of reward.