Unlock All Courses:
At the title screen enter: Hold L+R triggers then press X & Y.
Unlock Many Goodies:
To unlock all Skill Points, challenges and career mode tours, create a character with the name SafariTK. Note: This player profile will not work online.
Get 80 attribute points:
To play the game with the most skill points (80) available, you can do this in single player easily by creating a profile named "SafariTK". This profile can't be played online.