World 1-3 is the third level of World 1, and subsequently, of New Super Mario Bros.
The level starts off with a few tilting Mushroom Platforms where Mario can find a block with a Super Mushroom or a Fire Flower. In the next area, there are a few Spin Blocks that make the player Spin Jump very high. If the player Spin Jumps onto a platform higher in the area, it leads them to a bouncy mushroom below the first Star Coin in the level. The player finds a path of coins in the air. If the player follows the path, they are led to another Star Coin. After collecting that the coin, the player can go onto several tilting mushrooms in the air. The player can get the level's last Star Coin here. Afterwards, the player finds a Red Ring which makes Red Coins appear. There are also more mushroom platforms. There are then two more tilting mushrooms that lead the player to the level's pole.
- Star Coin 1 - Taking the first Spin Block brings the player to a second Spin Block. By using the second one, they can reach a bouncy mushroom where the first Star Coin resides above it.
- Star Coin 2 - After collecting the first Star Coin, the player must follow the trail of coins in the sky for the second Star Coin.
- Star Coin 3 - The final Star Coin can be found in mid-air between two erratically tilting mushrooms.