FreeRice is a great vocabulary game, and for every word you get right, 20 grains of rice are donated through the UN World Food Program to help end hunger. Everybody wins.
"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 of all ages, 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 60 levels in all, but it is rare for people to get above level 50."
So far, I've made it to level 48. What about you?