Math/Logic

Math Chalkboard
Brain Bashers a collection of brain teasers, puzzles, riddles, games and optical illusions. Thousands of puzzles and brain teasers, with something for every day, including games and optical illusions.

Central Intelligence Agency (CIA) Kids Zone -  The United States CIA offers challenges in puzzles and games.

Code.org - Code.org is a nonprofit organization and website that encourages people, particularly school students in the United States to learn computer science.

Chocolate Fix - Your goal is to add all the missing chocolate pieces to the chocolate tray

Greg Tang Math - Math challenge games

Laser Maze - Laser Maze challenges you to skillfully direct a laster beam around a small 5 x 5 board in order to light up one or more targets. 

Rush Hour - Object is to move the red car out the exit by moving as few squares as possible.

Set The object is to find a 'Set' in the 9 cards. A 'Set' is 3 cards in which each individual feature is either all the SAME on each card... OR all DIFFERENT on each card.