Body and Brain Connection

This is a pretty straightforward achievement. In order to unlock an Intermediate level, you have to score a C or better on the Beginner level of that Challenge, such as "Which Is Bigger?" in the Math category of Challenges.

There are five Challenge categories (Math, Reflexes, Logic, Memory, & Physical) with four Challenges in each.

To see your scores and to see which levels you have played and unlocked, go to "My Data" at the Main Menu, then select "Stats". This will show you a chart of your progress for every category and level.

Hope this helps!:)