Super Mario 64 Tips

Ice Slide Shortcut
First go to the Cool Cool Mountain and choose any star and go inside the cottage. Go down the slide and then when a line of coins go into the wall, follow them and you will find a path. You'll skip the rest of the slide and exit in the last room.

Don't do this when racing the penguin though or else he will accuse you of cheating and not give you the star.