Super Mario Maker for Nintendo 3DS is a port of the Wii U game, Super Mario Maker, allowing players to create and play their own Mario platform game levels, as well as play through many other previously-created ones.
The most drastic difference between this game and the original is the fact that the 3DS version does not allow for the players to upload the courses they create on the Internet. Players can, however, share their courses with each other via StreetPass or Local Play.
The game comes with 100 exclusive courses, not available in the Wii U version. These courses have different goals (like collecting every coin in the level, for instance), which will earn the player medals upon completion.
Almost every other aspect of the game remains the same as its Wii U counterpart, aside from a few details such as the absence of some small elements (like the Big Mushrooms and the Gnat Attack minigame).
Even though it is a 3DS title, the game does not feature stereoscopic 3D.