As you play a game on the Nintendo DS, you are allowed to save your progress so you can resume from that point at a later time. The DS provides two possible locations for saved data: directly onto the system memory or onto an SD memory card that can be removed and transferred between devices. When the memory becomes full, erase old data to create more free space for future games.
Turn on the Nintendo DS and wait for the menu to load.
Select "System Settings" from the menu, then select "Data Management."
Select "System Memory" or "SD Card," depending on where you saved the game data.
Select the game data you want to delete, then select "Delete."
Do not erase data you may want to use in the future. Data cannot be recovered after it has been erased.