when did new super mario bros come out
May 7, 2006
New Super Mario Bros.
Nintendo announced on February 21, 2006 that "New Super Mario Bros." would launch for the Nintendo DS on May 7, 2006. 
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New Super Mario Bros. [SEP] Development
Nintendo announced on February 21, 2006 that "New Super Mario Bros." would launch for the Nintendo DS on May 7, 2006. The game's new power-ups were also introduced at the same time, including the Blue Koopa Shell and the Mega Mushroom. Nintendo further mentioned that the game would be played in 2D but use 3D models to create a 2.5D look and feel. The May 7 release was later delayed towards May 21, but the game's release date was eventually only pushed back slightly to May 15; Nintendo also planned to release it around the same time that the Nintendo DS Lite launched, on June 11, 2006.