Tate Kids - Wondermind (Art + Memory)
ProProfs Brain Games
MENSA: Challenging Games for Kids
MENSA: Virtual Game Room
Arkadium - Card Games and Puzzles
Puzzles
NASA Kids Club
Chess Kids (No sign-up necessary!)
Sudoku for Kids
Daily Sudoku
Pic-a-Pix (Picross for Kids)
Game Puzzles for the Joy of Thinking
Scott Kim Web Games and Puzzles
Math Miscellany and Puzzles
Merriam-Webster Words Games
Mad Libs (Extra fun for Magnetic Poetry)
Sharp Brains - Brain Teasers, Games, and Illusions
Brain Food Lateral Thinking Puzzles
Brain Food Logic Puzzles
Brain Teasers and Optical Illusions
Rebus Puzzles