World 1 (New Super Mario Bros. Wii)

The Mushroom Plains of New Super Mario Bros. Wii has six levels, and a Grand Goomba who roams the map. Larry Koopa is the first boss to be fought in the game. This world features typical grassy plains and many different environments similar to New Super Mario Bros. and the first world in other games.

1-1 (The Grassy Plains)
The first level of the game is a generic grassland level. In the beginning of the stage just like in New Super Mario Bros., Princess Peach's Castle can be seen in the background. When the player starts, there are three ? Blocks, a few normal blocks, and a Goomba. The highest ? Block will hold an item, either a Mushroom or a Propeller Mushroom. The player must move to the right and they will see a moving piece of ground. Then move farther ahead and another moving piece of ground will be there. It has three platforms above it. It has a Green Pipe in it that moves around with it. Jump in it. In the underground area there are blocks, coins, and a P Switches. The player should hit the P Switch and collect the coins that were blocks. The P switch will lose its effect and the player can collect the remaining coins and head out the yellow pipe. If they are playing a Toad Rescue Mission a Toad should be yelling out from the ? Block behind them. The player can head forward to find their first checkpoint. Then they should hit the ? Block to get a Propeller Mushroom and get the Star Coin in the air. Go past the two pieces of moving ground and hit the second ? Block for another item. Spin upwards using the Propeller Mushroom and go through the Red Ring. Collect the Red Coins and continue forward. At the end of the platform spin to the next one and then skip the next one with the red Koopa and collect another Star Coin. Jump off the left side of the platform and find the moving piece of ground. Wait for the Green Pipe and jump in it. Alternatively, the player could stay in the "compartment" and get three 1-Ups and dozens of coins. If the player went in the pipe, wall kick up, collect the last Star Coin and head out the yellow pipe. The player will be in a hidden area. Just before leaving the hidden area there is a block, hit it and collect the 1-Up Mushroom. Continue forward and complete the level.

1-2 (Creepy Cave)
This level takes place in underground. Special power-ups and items include Ice Flowers, Fire Flowers and POW Blocks are used there. Right about where the halfway point is, there is a way to get infinite 1-ups. The player must jump into a cave, grab a star, and kill all the Koopa Troopa s and Pirahna Plant s in their path.

1-3 (Yoshi Heights)
This is the first stage to feature Yoshi, along with the Hammer Bros. The first Star Coin is located a tiny bit after the player finds Yoshi. The best way to get it was to flutter jump off the ground with Yoshi, or just to dash and jump to the coin. The second coin is found deeper in the level, where there will be three green pipes with Piranha Plants. Next to the third pipe will be a hidden passage, where this pipe leads down to a underground tunnel. The coin will be found there. The last star coin is near the end, way too high for Mario, Luigi, Blue Toad, or Yellow Toad to just jump up. The player should do one of the following opinions: use Yoshi to flutter jump off the nearby pipe, jump with Yoshi under the coin and shake off of him, or wall jump off the nearby pipe mentioned before. The player must then continue down the course until he/she reaches the flagpole and completes the level.

For the secret entrance, the player should go back just a tad bit before the last star coin. The player needs to jump to the high cliff edge leading to a hidden passage. Using Yoshi is the best. Once the player reaches the entrance point, he/she needs to jump over the passage, above the screen, and travel down the path following it. Near the end of this path will be a secret pipe, which will send the player to the secret flagpole. The secret exit will take the player to World 1's warp cannon, which sends him/her to World 5.

World 1 Fortress (Larry's Tower)
This is the first stage where Larry Koopa is fought. When the level starts, a brown block will go up and down where there will be a ? Block. It will have an Ice Flower in it which can change Mario to Ice Mario. At the top, there will be a Dry Bones walking left to right. Another brown block that goes up and down is nearby. A blue platform will appear so the player can wait until the pendulum will be swinging by them. Once the player gets to the two platforms, there will be another Dry Bones. If it goes to the brown block it will push the Dry Bones. When the player goes up the two brown blocks there will be another brown block to go to the pendulum. It will have a ? Block that will have an Ice Flower. There are two ways to get to the other side. If the player goes to the left, he/she will have to wait until the brown block opens. At the top, the player will find coins and a Star Coin. If the player goes to the right, there will be two Dry Bones and three pendulums. Four brown blocks will be available at the top. The last two brown blocks can smash the player. After the player jumps to the top, there will be a section. There will be two blue platforms which the player can wait until the 4 brown blocks move away. The player(s) have to be careful because they might get smashed. At the top, there will be a block that can get the player a Propeller Mushroom, a Mushroom, a 1-Up, or a Star. On the pendulum, there will be two ways to get to the top. Once the player gets to the top there will be 4 pendulums. There will also be a Red Ring which if you get all 8 red coins you can get a 1 Up. There will be 4 brown blocks. 2 of them go to first. Eventually the other 2 will pop out. When the player gets to the top there will be 2 brown & 2 ? Blocks. The red door will open & the first fight begins. If the player has Fire Mario, he can hit Larry with fireballs which will stun him. Eventually he will retract into his shell trying to hit the player. The way to defeat him is to stomp on him three times while avoiding any of his attacks. If the player defeats Larry, he/she can proceed to level 1-4.

1-4 (Lake Diving)
This is the first Underwater level in the game.Cheep Cheeps,Urchins,Mega Cheep-Cheeps,Deep Cheeps,Clams and Spiny Cheep Cheeps appear. At the beginning there are two Cheep-Cheeps that must be frozen so that Mario can get to the ? Block which will get him an Ice Flower. There are many bubbles flying around that can push Mario into walls.

The next area also has Deep-Cheeps which must be frozen along with the Cheep-Cheeps. There is also another ? Block with another Ice Flower in case Mario has lost his previous one. On the land there is a Red Ring which will make lots of Red Coins for Mario to collect. There is also a checkpoint flag. In the next area there is a roof so Mario must freeze the Urchin and it will break the roof allowing Mario to get through. There is also a Star Coin which is guarded by a Mega Cheep-Cheep that Mario must freeze to get past. In the next area there is a room which has a Spiny Cheep-Cheep that will follow Mario. He must destroy that Cheep-Cheep and then get the 1-Up Mushroom at the bottom of the screen. There is also a Fire Flower and a Starman. Mario must then go through a Red Pipe. Many Cheep-Cheeps populate the next area so Mario has to use his Starman to destroy as many as possible and then go through the green pipe. Then there is a Koopa Paratroopa that Mario can use to land on the flag at the end of the level.

Enemy Course

 * Eight Goombas
 * Four Grand Goombas
 * Two Mega Goombas

1-5 (Mushroom Heights)
This is the first sky level. It mainly features cube (square) platforms that rotate in one direction.

1-6 (Donut Plains)
This level is called donuts because of the many donut shaped pieces of land there is here. At the beginning you must jump over all the donuts at the halfway point, there is a donut. If you jump to the wall on the left, there is a secret pipe that takes you to an underground cave with a star coin. You will then navigate through a maze of Pirahna Plants and donuts. Touch the flag to beat the level.

World 1-Castle (Larry's Castle)
This is the first Castle level, filled with a lot of lava in the game and features many gear-shaped platforms. Thwomps and Super Thwomps make their only main appearance in this castle.

Larry Koopa is fought again here.

Enemies Introduced

 * Goombas
 * Koopa Troopas
 * Koopa Paratroopas
 * Piranha Plants
 * Venus Fire Traps
 * Hammer Bros.
 * Dry Bones
 * Cheep Cheeps
 * Mega Cheep-Cheeps
 * Spiny Cheep Cheeps
 * Deep Cheeps
 * Mega Deep Cheeps
 * Cheep Cheep Schools
 * Clams
 * Thwomps
 * Super Thwomps
 * Podoboos