Here is a classical problem.

You got 9 dots.

The challenge is to connect them all in four straight lines, without lifting the pen or pencil from the page

.   .   .

.   .   .

.   .   .

It is one of the classic lateral thinking puzzles. When you figure this one out you will have a new appreciation for the expression “thinking outside of the box.” Lateral thinking puzzles like this help you increase your brain power by getting you out of thinking “ruts.” They habituate you to creative thought as a normal function of thinking and problem solving.