Star Coins are collected throughout New Super Mario Bros. for the Nintendo DS portable game system. There are 80 levels, each with three Star Coins, for a total of 240 coins. The difficulty to obtain them varies by the level.
Acquire the first Star Coin
The first Star Coin is located roughly one-third of the way through World 2-4. Climb up the right side of the pyramid. Slide under the low ceiling to access a passageway, which leads to the first Star Coin.
Obtain the second Star Coin
The second Star Coin is located a short distance after the checkpoint. Go down the yellow tube at the bottom of the pyramid. Demolish the Brick Block, then walk to the right. Be cautious of the attacking Goombas. Ride the platform to the bottom room, where you find the second Star Coin.
Procure the third Star Coin
The final Star Coin is located near the end of the level. Avoid jumping down the pit full of coins leading to a yellow tube, which brings you to the ending flagpole. Jump over the coin pit, and keep walking to the right. The third Star Coin is located in the indention in the wall.