Star Coin

A Star Coin is a collectible in New Super Mario Bros. In every level (numbered, lettered, towers, ghost houses and castles), three star coins appear per level. Some are easy to grab, while others require special power-ups (such as the Mini Mushroom or Blue Koopa Shell) to access. There are eighty levels, thus there are two hundred and forty star coins to find in the game. Each star coin adds 1000 points (same as a power-up) to the player's game score.

Uses

 * Opening signs on the world map. Little picket signs block bonus paths that may lead to Toad Houses or to alternate, lettered levels. There are thirty-two signs in the game, each costing five star coins to open. Also, after opening the signs, the player is given the option to save, allowing them to easily save their progress instead of having to play through a fortress or castle.
 * Buying new backgrounds. After beating the game once, a blue Toad House will appear above Level 1-1. There are four bonus backgrounds for the touch screen that cost twenty star coins each (the last background can be unlocked by opening every Toad House).