Once in a while you need to wake up your brains and give them some new information. This is how the brains stay active and you can learn better. This is for younger and older people as well, because you're never too old to learn. Test your memory with games in which you need to remember things, like the famous Memory game or Remember Colors. In the Hacking the Vault games you have to think well about the actions you need to take. Are you curious how smart you are? Test it in the IQ tests.