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FreeRice has two goals:
Provide English vocabulary to everyone for free.
Help end world hunger by providing rice to hungry people for free.

How does the FreeRice vocabulary program work?
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 55 levels in all, but it is rare for people to get much above level 48.

How is the difficulty level for each word determined?
The program keeps track of how many people get each word right or wrong, and then adjusts each word’s difficulty level accordingly. So the words at the easiest levels are the ones that people most often get right. The words at the hardest levels are the ones that people most often get wrong. As more and more people have played the game, these levels have become increasingly more accurate.

No more word a day calendars.