Freerice.com is awesome.
According to the website, Free Rice has 2 goals: 1) Provide English vocabulary to everyone for free 2) Help end world hunger by providing rice to hungry people for free.
Two straightforward, admirable goals combined. And the site is equally straightforward. A word pops up at the top of the screen along with 4 possible synonyms… and you choose which you think is correct. Each time you get a word right, not only is the next word a little tougher, but they donate 20 grains of rice. It doesn’t take long to start adding up. As an ad-financed site, certainly the aim of the game is to get you to spend more time on the website, thereby allowing their advertisers more views… but I am just so taken with the ability to make the world better in two such delightfully simple ways… the philanthropist and the logophile in me can’t help but wish that the site is efficacious.