A guide to completing World 5-6 in Super Mario Bros 3 for the Nintendo Entertainment System.
How to Clear World 5-6
This level automatically moves to the left, so be careful not to get crushed by a wall or pushed off a platform.
Jump on top of the stack of wooden blocks, and you will start to see Para-Beetles flying from the right. If you jump on top of a Para-Beetle, you can use it as a platform. It will float slightly downward, then will fly up and to the left. Make sure to jump off of it before you reach the edge of the screen, because you will fall off or get crushed by the beetle itself if you reach the edge of the screen.
Jump from beetle to beetle, and try to get the coins above them.
Eventually you find a ? Block that contains a Super Mushroom or Super Leaf. After that, there is a Red Paratroopa, and the Para-Beetles will stop appearing.
To the right, jump onto the Note Block and press the jump button at the correct moment, and you will jump high up, where you can get the coins up above. Use the next Note Block to get the rest of the coins.
After that, there is a brick platform, with a smaller brick platform beneath the right side. Jump down onto the smaller platform, stand on the leftmost brick of the smaller platform, and jump straight up to reveal a P Switch. Step on it, then quickly go to the right to collect the stacks of two coins on top of the bricks before the bricks turn back into coins. You will also have to dodge (or stomp on) a Flame Chomp in this area. After the stacks of two coins, there is a platform of bricks that you can safely stand on, because the upper layer turns back into coins and the lower layer turns back into bricks when the P Switch wears off.
From there, go through the pipe on the right. Then go to the right, avoiding the Spiny Eggs from the Lakitu, and hit the Goal Block to complete the level.
After the Level
You can visit the Toad House for a chance to get a Super Mushroom, a Fire Flower, or a Super Leaf.
If the Hammer Brother is in your path, you can fight them to get a Music Box.
Then you can either go to World 5-7 if you haven't cleared it already, or the second fortress of World 5.