Course 4 is located near the left side of the Castle's first floor. From the entrance of the Castle, walk forward to the base of the large red stairwell. Go to the left of the stairs and enter the door that has a yellow star with the number three on it. Once inside the small room, go forward and jump into the center painting of the snowman. You need three Stars to enter this course.
Star 1: Slip Slidin' Away
Jump on top of the cabin near the entrance of the course, then enter the chimney. Once inside, slide down to the bottom of the Snow Slide, then exit through the wooden door and collect the Star. If you are having difficulties safely reaching the bottom of the slide, there's a shortcut that will make things a little easier for you. The shortcut is located in the first tunnel you pass through. While sliding through the tunnel, look for a row of five Yellow Coins that are lined up in the direction of the right wall. Follow the path into the wall to locate a hidden passageway. This shortcut will take you straight to the end of the slide.
Star 2: Li'l Penguin Lost
Go to the top of the mountain and pick up the Baby Penguin, then carry it to the bottom of the mountain. Bring the Baby to its mother and she will give you the Star. To get to the Baby Penguin: From where you begin Course 4, jump up onto the Cabin's chimney, then jump up to the top of the mountain. Stand next to the Baby Penguin and press the A Button to grab onto it. To return it to its Mother: Slide down the mountainside until you reach the wooden bridge with the two jumping Snowmen. Carefully walk across the wooden bridge, then continue down to the bottom of the mountain. With the Baby Penguin in hand, talk to the Mother Penguin to receive the Star.
Star 3: Big Penguin Race
Race the Big Penguin down the Snow Slide to win a Star. Jump on top of the cabin near the entrance of the course, then enter the chimney. Once inside, talk to the Big Penguin and agree to race him down the Snow Slide. If you win without cheating, the Penguin will give you a Star. Practice is the key to winning this race. If you re-enter the Star 1 objective, you can practice reaching the bottom of the slide. To quickly reach the bottom, hold forward on the Control Pad and avoid touching any of the walls.
Star 4: Frosty Slide for 8 Red Coins
There are eight Red Coins scattered throughout the course. Six are found out in the open, one is located behind the ice column near the center of the mountain, and one is located at the top of the tram. After you collect all eight Red Coins, the Star will appear on the other side of the broken rope bridge near the center of the mountain. You can collect the eight Red Coins in any order. One is encased in ice near the entrance of the course. One is encased in ice by the ice wall on the mountainside. One is located near the big Snowman at the bottom of the mountain slide. One is located above the snow covered tree near the Mother Penguin. One is located on the other side of the wall to the right of the Mother Penguin. One is located on the small platform underneath the mountainside. One is located at the top of the tram. One is located on the broken rope bridge near the jumping Snowmen.
Star 5: Snowman's Lost His Head
>From where you begin Course 4, jump up onto the cabin's chimney, then jump up to the top of the mountain. Go left. Drop down to the wooden platform and talk to the Snowman's body. The body will start rolling down the mountain slide. Race the body down to the Snowman's head at the bottom of the mountain slide. You cannot take any shortcuts. If you jump off the mountainside, the Snowman's Body will not follow Mario into the Snowman's head. Quickly stand to the left or the right side of the Snowman's head and wait for the body to bounce into the head. If it doesn't work, restart the objective and try it again. Afterward, talk to the Snowman to receive the Star.
Star 6: Mario's Super Wall Kick
If you haven't spoken with the Pink Bob-omb yet, you must first do so. Then, enter the Cannon near the base of the tram. Move the crosshairs down and left until you see a ledge with a snow-covered tree on it. Aim the crosshairs so the center is about two inches above the tree, then shoot out of the Cannon. If successful, you'll grab onto the tree; if not, try again! Follow the narrow path around the mountain, then Long Jump over the large gap. Continue up the path, then back to the right until you reach a blue wall. Wall Kick off the blue wall and land on the ledge to the left. Continue up the path and time a Double Jump so that the second jump is near the end of the path. If timed correctly, you can then Wall Kick off the upper portion of the wall and land on the ledge to the right. Carefully walk across the icy bridge and collect the Star.
Star 7: Switch Star of Cool, Cool Mountain
You need to play as Wario to collect this Star. Go to the bottom of the mountain and jump onto the tram. Ride the tram halfway up, then jump onto the small floating island with the Pink Bob-omb. Step on the Star Switch, then jump off the island towards the Mother Penguin to ride the air current towards the Star. Continue forward to a frozen pond with the Star inside. Stomp the ice to destroy it and collect the Star
Star 8: Collect 100 Coins
You can collect 100 coins using any of the Star objectives. You'll find 154 coins on the course. A Blue Coin equals five Yellow Coins. A Red Coin equals two Yellow Coins.