Secret Course 05
From the Super Mario Wiki
The entire course consists of a single room with an arrangement of eight soft platforms along with a single Hard Block and a door. There is also a trail of coins that moves around the room. One of the Bonus Medals is at the bottom middle of the room and another one is found right above it after touching the outline. A third Bonus Medal is found at the far right side above the bottom right soft platform. The final two Bonus Medals are at the top of the room and can be obtained by jumping from the Hard Block. The course ends once the player enters the door.