The Frog Song Skip allows you to skip playing the Frog's Song of Soul to the Turtle Head in order to enter Turtle Rock (D8). Together with the Rooster Skip, it theoretically allows the Frog's Song of Soul to be skipped in a speedrun. However, the Frog Song Skip is extremely luck-based and precise, and thus would most likely not be feasible in an RTA, and it is not allowed in the most common any% category.
Kill the crow to slightly clip into the rock.
Leave the screen before the crows death animation is over (this causes it to respawn because it didnt die).
Re-enter the screen and glitch the crow to the other screen.
Kill the crow (which clips you further into the wall. If you move at this point youre screwed.)
The crow needs to drop an item that is barely in range of the screen so that you dont pick it up as it drops.
The following events have to happen before the item that the crow dropped disappears:
The moblin has to get in range so that you can hit him with the hookshot. This causes you to clip further into the wall.
Now you have to hookshot the item the crow dropped to clip even more into the wall.
The moblin has to drop a heart and you have to hit it with the hookshot at its highest point to fully clip through the wall.