Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. For example, observe that 4 times a number is always even, and explain why 4 times a number can be decomposed into two equal addends.

When we're adding and subtracting, do evens make odds into evens? Do odds make evens odd? Which one has… *more power!?*

The commutative and associative properties are a *whole lot* more interesting when you apply them to a mathematical operation that you created!

Say you have a dollar. Say you can double that dollar each day: $1, $2, $4, and so on. How long will it take to reach… **one million dollars**? Not as long as you might think!