New Super Mario Bros./World 7-4

Nowhere in the Mushroom Kingdom do any mushroom platforms grow as tall as the ones in this level. In this relatively short stage, you'll be using Spin Blocks and mushroom platforms to climb higher and higher and higher still. You should be able to complete the stage fairly quickly, but a missed jump can mean losing a ton of progress into the stage.

Level walkthrough
You will start at the very bottom of the course, with plenty of Spin Blocks surrounding you and mushroom stems rising skyward in the background. You can go straight for the exit from your starting position, but for total completion, you'd want to head right first. Once you reach the right wall, jump from the nearby Spin Block up to a mushroom platform above you. The first Star Coin is hovering above this first platform, and you can use the Spin Block beside the platform for more height when getting it.

Now, launch yourself from the Spin Block to the right of the platform below the first Star Coin. Start moving left at the peak of your jump until you're above a pink bouncy mushroom. Bounce off the pink mushroom to an even higher mushroom platform to the left, where you can get the second Star Coin. Make a running jump toward the Spin Block to your left. Launch yourself from it, then use the pink mushrooms to make you bounce up higher until you land on a thick red mushroom platform, where the checkpoint is activated.

Get to the Spin Block and launch yourself up with it. If you hover to the right as soon as you do, you can go through a red ring that triggers red coins in a noticeable trail back on to the thick red mushroom and around it. Jump from the Spin Block again and this time drill into the pink mushroom to your left. Bounce up high and start moving right to get the final Star Coin, and keep holding right, following the trail of coins. You will eventually see a pink mushroom below a pipe. Bounce up into the pipe with the mushroom.

In this ending area, there is still a secret to be discovered. Hit the block on the right wall to make a vine spring out, then attempt to outspeed it by jumping from the Spin Blocks. You should see three more brick blocks at the peak of your second Spin Block jump. Drill through the blocks to let the vine continue to grow, letting you climb to a hidden red pipe that takes you to a bonus area. In it, use the Spin Blocks to reach the ceiling of the area and hit the P-Switch to spawn a ton of silver coins. Fall down following the coins and into the yellow pipe at the bottom. Go right to the flagpole to end the course.

Star Coins

 * 1) Go right from the start until you hit the wall, then use the Spin Block to launch yourself upward. The Star Coin can be found hovering above a mushroom.
 * 2) Jump up from the Spin Block to the right of the first Star Coin, then bounce on the pink mushroom above to reach an even higher platform with the next Star Coin.
 * 3) After bouncing from the tallest pink mushroom, simply hover to the right. The Star Coin should be right in your path.

Alternate exit
You'll need to be in your Mini form for this secret exit. Once you've bounced from the tallest pink mushroom, look for a flying block near a wall to your left and land on it. Jump to the narrow alcove, then make a jump to loop around the wall above the alcove and drop into the small valley with the mini warp pipe. Take the warp pipe to get to the red flagpole.

This secret exit skips straight to the World 7-Castle, letting you skip the confusing network of levels that comprise the second half of World 7 and opening a green Toad House as well.