Uncle Norm’s boss gave him an important top secret mission: and it involves sending the Normbot on a secret mission all around the world - but it’s all very hush hush. Now it’s up to Uncle Norm to find a way to conceal the top secret message that is travelling with the Normbot. He enlists the Rads to help, and soon they’re on the trail of a professor who knows all about codes and how to encrypt information. Together, they come up with a fun and simple cipher for hiding the message …so the secret will never fall into the wrong hands! Bon Voyage Normbot!

The Gist: Letters are used in algebraic expressions (or formulas) to represent different numbers. To find the value of an expression, we substitute a number for a letter. In this episode, we introduce the concept simple substitution principles.