Super Mario Brothers 3 NES Cheats

Change forms
Press Select while playing a normal game to change into different Marios or Luigis (Mushroom, Fire Flower, Super Leaf, Frog, Tannokie, and Hammer Brother).

Getting the boot
Hold Y and press Select.

28 P-Wings
Complete the game, then press Start at the ending screen. The next game will begin with 28 P-Wings per brother.

Random world
Wait until Mario and Luigi begin running around during the opening sequence. Press random buttons on the controller. The game will begin at a random world after the number of players are selected.

Whistle Room
Go to world 1-3. Towards the end of the level, there should be a white rectangle floating in midair. Jump on it, then squat down. In a few seconds, you should fall through. Go to the end of the level. In a few seconds, you should see either Mario or Luigi { which ever Mario Brother you are } on a platform on the left side, and a Mushroom Person on the right. In the middle of the screen, there should be a box. Run to the box, and press B. A whistle should pop out. To use the whistle, you should be on the level select screen. Press B, and there at the bottom of the screen in a pink strip should be a whistle. Scroll over to it and press A. It will take you to a Warp Zone. Choose a world and press A. You can use your whistle in that game only.

Double Warp
Receive two whistles and use one to get to the warp room. In the warp room use the second whistle which will take you to the last part of the warp room. This will get you to level 8 to defeat king Koopa.

Desert World Whistle
Towards the end of the Desert World you can obtain another whistle. In the top right corner in the far right hand corner of the world there is a rock directly next to the path. Use the hammer you obtained from one of the Koopa Battles to break it. Once you've found it though you must defeat two fireballs spitting Koopas to get it make sure you at least have a mushroom before going into this battle just to be safe.

Warp Whistle II
In world 2, after you beat Level 4, there is a stone right beside 4.Use the hammer and then there is a path that opens up. Fight the fire brothers and after you do that in the box is the Second Whistle.

Hammer Suit
The hammer suit will make you invulnerable to fire and you can kill ghosts with your hammers.