FreeRice has a custom database containing thousands of words at varying degrees of difficulty. There are words appropriate for people just learning English and words that will challenge the most scholarly professors. In between are thousands of words for students, business people, homemakers, doctors, truck drivers, retired people… everyone!

FreeRice automatically adjusts to your level of vocabulary. It starts by giving you words at different levels of difficulty and then, based on how you do, assigns you an approximate starting level. You then determine a more exact level for yourself as you play. When you get a word wrong, you go to an easier level. When you get three words in a row right, you go to a harder level. This one-to-three ratio is best for keeping you at the “outer fringe” of your vocabulary, where learning can take place.

There are 50 levels in all, but it is rare for people to get above level 48.

• Click on the answer that best defines the word.
• If you get it right, you get a harder word. If wrong, you get an easier word.
• For each word you get right, we donate 10 grains of rice to the United Nations World Food Program.

Ten grains of rice may seem pretty cheesy, but FreeRice began on October 7th, 2007 and as of 14 November they had donated 1,897,053,670 grains.

http://www.freerice.com/