You've surely heard of the acronym PEMDAS for the order of operations (Please Excuse My Dear Aunt Sally) - standing for Parentheses, Exponents, Multiplication & Division, Addition & Subtraction.
There's a new game for order of operations called My Dear Aunt Sally. You can play it free online, or purchase an inexpensive app for your tablet.
It's a very good game, and takes some thinking! You need to place the given numbers into two expressions so that the operations make the two expressions have the same value.
Here are some screenshots. The first one is the easiest level. The addition on the top has to have the same value as the multiplication/addition expression on the bottom.
It gets harder if you choose to include exponents:
You can also choose to use fractions, so it becomes harder yet: