New Super Mario Bros. Wii 9-3 -- Bullet Bill Barrage

This level is crawling with homing Bullet Bills. They will target you and chase you all over the level. While being chased by Bullet Bills, there are a series of red Koopas on their own segments of land. In the 4th gap is a green pipe, which will take you to the 1st Star Coin. It's a maze and you have until the P-switch runs out to clear the blocks turned into coins in front of the Star Coin. The easier way is to go to the right instead of the left. Near where you exit the pipe is a pipe overhead to the 2nd Star Coin. I reached the pipe with a Propeller Suit that I got in another level. I used the P-switch to create blocks so I could reach the 2nd Star Coin. In the long stretch to the goal, there are several moving yellow platforms we must negotiate while dodging "homing" Banzai Bills. They won't chase you, but they will approach you instead of going in a straight line. The 3rd Star Coin is in this area. I kept going to the goal through the pipe. This took me 18 tries.