The next time you reach for your smartphone to play the latest cartoon game app, try out one of these interesting online puzzle games instead. They’re just as fun and addictive as those racing games or bubble breakers, but they stimulate your brain just as much as your senses.

Riddles Hub
Riddles Hub expands on the popular riddles you loved as a child, offering a whole database full of word problems that will really make you think. Each riddle describes an object or a person, and they’re all organized by categories like logic, match, alphabet, relationships, or words. If you’re stumped by a riddle, Riddles Hub also offers helpful clues to point you in the right direction before you give up.

The Cyclopedia of Puzzles
This online collection of tricky math puzzles features 5,000 puzzles, tricks, and conundrums. Taken from a 1914 book created by Sam Lloyd, these puzzles all appear in their original forms on photocopied pages. If you love history and mathematics, The Cyclopedia of Puzzles offers a little bit of both.                           

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