Place first in each of the first three circuits at the Amateur difficulty level to unlock Dewey as a playable character.

Place first in each of the first three circuits at the Intermediate difficulty level to unlock Louie as a playable character.

Win each of the first three circuits at the Professional difficulty level to unlock the Victory Vehicles circuit of Yellowstone, Everglades, Malibu and Washington, D.C.

Do yo own the Gameboy version of this game too? How about a Transfer Pak? You do? Place your Gameboy version of the game into your Transfer Pak. Place your Transfer Pak into your N64 Controller and turn on Mickey's Speedway for the N64. By having your Gameboy version in your Transfer Pak you can now select Huey.

There are 4 missing car parts that the Weasels have stolen and hidden on various tracks. If you find each of these it will unlock Frantic Finale.(And you don't have to finish the race first or anything, if you find a car part just select quit.)