Super Mario 64/Cool, Cool Mountain

Cool, Cool Mountain is in the main room of the castle, in the door on the left, below the door for Bob-omb Battlefield. 3 stars are required to access it. The level is set on a snowy mountain, though be aware that you can fall off and die.

Star 1: Slip Slidin' Away
This star is obtained by entering the chimney near the start of the level and completing the slide without falling off. At a certain point, a row of coins points toward the wall; go along them to pass through the wall and you will enter a secret passage that has 3 1-ups and no risk of falling. Other shortcuts require looking at the map to find where some slide lines intersect.

Once you reach the bottom of the slide, go through the door to find the star waiting outside.

Star 2: Li'l Penguin Lost
On the snow-covered platform next to the chimney for the previous star, there is a blue baby penguin. Pick it up by pressing B and take it to the mother penguin at the bottom of the mountain. Getting hit by an enemy or falling far will cause you to drop the penguin, which becomes harder to pick up as it moves around.

Once you bring the baby penguin back to its mother, she will give you the star.

Star 3: Big Penguin Race
Go in the same chimney as for Slip' Slidin Away. There will be a large penguin waiting; he will offer to race you. Accept, and get to the bottom of the slide before he does. Taking the shortcut mentioned above is considered cheating.

Once you beat the penguin (without using the shortcut), he will give you the star.

Star 4: Frosty Slide for 8 Red Coins
Collect the eight red coins spread around the level; then, get the star. There is a broken bridge where you start. Have Mario walk to the very last step on the bridge and he will be transported to the very bottom where the Mama penguin is. You can also transport back up to the top when you get the coins on that level. Then take the slide again to get the other coins. The hardest red coin to get is under the slide, where you see the second row of gold coins. Walk, don't slide at that point, ( you can make him walk by doing a little jump when you start to slide), then jump off of the slide, over to the right and onto the ledge below where the coin is hidden behind the sheet of ice. Before you jump down to that ledge, be ready to hold Z and move Mario forward so he won't slide off, because it is very slippery down there. Get the red coin, then go toward the box with the life. Get the life and proceed in the same direction and jump off where the giant snowball head is. Continue to find the coins... one is just around the corner. The other coin is just over the edge where the elevator comes up from the penguin level. Go where the two snowmen are jumping on the bridge and cross the bridge. Get a side view of the bridge as you go across and time the jumps where you can run under them as the snowmen are in the air. Don't touch them, just run under. You will see another coin after you go across the bridge... go a little past the ledge and jump up to it to assure that you will have enough room without falling off... Walk carefully to the end of the bridge and get that coin. After you have found all 8 coins, the easiest way to get the star, is go on to the bottom level, then transport yourself on the broken bridge back up to the top where you started, then take the slide to the left again, but this time, watch when you get to the curve just before you make the last sharp turn to the left. Jump to your right across to the other side. When you get on that level, you can easily jump right down and get the star below it.

Star 5: Snowman's Lost His Head
Go up on the platform next to the chimney, then straight to a wooden platform. This platform has a pedestal with a ball of snow on it. Approach the ball and it will talk to you, then start rolling down the slide. Go in front of it, but do not get too far ahead of it. Slide then run to the pedestal with the snowman's head. The ball will follow you so stand on the left side of the snowman's head to make a complete snowman. The snowman will then give you the star!

Star 6: Wall Kicks Will Work
Activate the cannons if you have not done so already by talking to the pink Bom-omb on the platform halfway up the lift on the bottom of the mountain. Then, take the cannon and aim toward the ledge directly across. Try to catch on the tree by aiming above it. Then, run down the narrow ledge, defeating the enemies along the way by punching them. Long-jump across the gap.

Then, go to the lowest part of the platform above Mario, and either wall-kick or somersault onto it. Then, go near the high end. Run backwards a bit, then run up again and right away jump so that you somersault. You need to hit the vertical part of the wall. If you do, then just as you hit the wall, press A to do a wall kick and push the stick to the right. If done correctly, you will land on the top platform. Then, walk across the narrow ice path (carefully) and jump to get the star.

An alternative method is to go down to the platform where the snowman's body was before. Jump on the the enemy there to fly and float down to the star.

Star 7: 100 Coins
It is definitely possible to get 100 coins at this level. You can get 80 alone on the slide at the beginning of the level and then get the rest of the 20 around the level.