Rotating Block
Rotating Blocks, also known as Flip Blocks and Turning Blocks, are yellow, eyed blocks found in Super Mario World. When hit from below, they spin around, allowing Mario and Luigi to pass through them. Super Mario and Super Luigi can destroy them by using the Spin Jump from above. They seem to replace Brick Blocks from previous Super Mario games. Some blocks disguised as Rotating Blocks have items inside like ? Blocks.
Rotating Blocks reappeared in Super Smash Bros. Melee (as well as the remake in Super Smash Bros. Brawl), on the Yoshi's Island stage. In this game, Rotating Blocks were identical to their Super Mario World counterparts, only they were 3D (they would turn 2D when rotating). They also showed up in Super Princess Peach, where they looked the same but had a different purpose: rather than rotating when hit, they would sometimes drop an item. Also, the Boards of Super Mario RPG: Legend of the Seven Stars and Bike Pads from Mario & Luigi: Superstar Saga bear resemblance to Rotating Blocks.