Dino Domain Ancient Lake Stage- When you start, go straight. Look straight
ahead, you can see the key located on a ramp right in front of you,
in between two Stonehenge like monuments.
Snowflake Mountain Snowball Valley Stage- When you start, don't move ahead.
Turn left immediately and go through the path in the mountains.
Then take another right and you should see the key in an a cave
in the side of the mountain.
Sherbert Island Crescent Island Stage- After you pass the first Zipper
on the left branch, take off into the water. Pass the Zipper
and float out into the water. Swing right to find the third
key hidden in a little inlet.
Dragon Forest Boulder Canyon Stage- After passing over the
drawbridge, grab a Turbo boost and turn around. Line up with
bell (you'll hear a chime) and then drive underneath it. The
drawbridge will lift and you'll need to hit your Turbo to help you
grab the key at the bridge's top.