Extra Lives:
In the second warp room in front of the level "Bear It", jump on the cute little polar bear 10 times and he will give you 10 extra lives!

Boss Warp:
To go to the next or previous boss, press and hold L1, L2, R1, R2, and Triangle when standing on the middle platform of a warp room.

Gem Hints

On the Bee-Havin level 20 about 2/3 through the level there is a stack of Nitro's. Climb up them and you will be able to get the Purple gem.

These are for the colored gems.

Turtle Woods: You have to get no boxes (Blue Gem)
Snow Go: Get the warp for Snow Go and at the end of it is the Red Gem
The Eel Deal: Go past the Nitro Boxes at the Dead End and go through the wall. (Green Gem)
Plant Food: Get no boxes and beat the timer

Hidden Warps:

1. Beardown: the small ice floe at the end of the stage
2. Aircrash: the second river, don't jet ski, but jump on the boxes to the platform
3. Unbearable: when the cub bucks you off, go back until you see him again.
4. Hangin' out: when you drop down a hole into some eel-less water go into the foreground and drop down a hole. use R1 to make crash pull up his legs.
5. Diggin' it : near the end there is a spitter plant on a circular platform. Belly flop onto it.