Check out freerice.com. The site will give you a word and 4 choices. If you choose the correct definition, they will donate 10 grains of rice through the UN.
Why should a student care? If you will be taking the SATs, GREs, GMATs, LSATs, MCATs, or any OTHER standardized test you will get a better grade if you know more vocabulary. Here is a way to learn some more and help people at the same time.
Rebecca is a PhD student who is blogging about her academic experiences at protoscholar.com