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Order of Operations GameA very cool activity, and a fun way to practice the order of operations. http://www.learnalberta.ca/content/mejhm/html/object_interactives/order_...
One to TenThe computer randomly chooses 4 digits. Use the four digits and the arithmetic functions  Addition, Subtraction, Multiplication and Division (and also Exponents and Parenthesis) to form the numbers from 1 to 10.
Connect Four: Order of OperationsThe classic Connect 4 game, but students have to first correctly evaluate the numerical expresson before they are allowed to drop their chip.
The Numbers GameA game styled on the British TV show Countdown, where contestants used 6 numbers and the usual operations and brackets to make the target number. This program has a great bonus  after you have found a solution (or not), the program will then list all of the solutions. It can be a rather humbling experience.
Make 24You are given 4 cards, the operations +, , x, / and brackets. Your task is to construct an expression using all 4 cards that evaluates to 24. Oh, and you have to find an answer in less than 1 minute. Initially this task is can be very challenging, but the more problems you try, the easier they become. From Cool Maths.
Order of Operations TINspire documentA multipage TINspire document on the order of operations. It includes a series of interesting and challenging activities.
The Countdown Game, and Number and LettersThe Countdown Game is a great way to review Mental Computation and the Order of Operations. Highly recommended. Numbers and Letters is a variation of the Countdown Game that has additional controls for classroom use.
