Collect all the coins from every level.
To unlock Gold Yoshi, get all levels in time trial mode. Then, in time trial mode, get all coins and place first in top five, with all levels. Finally, complete story mode without dying and find black and white Yoshi.
Mario Paint theme song
Enter the "Time Trial" menu and listed to the game theme eight times.
Locate and get a white Shy Guy. Complete the current level and enter the character selection screen for the next level. Select the Shy Guy to restore one of the dead Yoshis. Note: If no Yoshis have been lost, the white Shy Guy will not appear.
Shrink in "Piranha Groove" (level 4-4). Hit an egg block while shrunk to create a very small egg. Take it while still shrunk. The egg will remain small as you return to normal size. Note: The mini-egg is still as powerful as the full-size version.
If Yoshi is low on eggs, is not next to a egg block, and super happy, prepare to fire an egg but cancel that action. Yoshi will put the egg into the inventory and allowing it to be kept.
Pop bubbles without an egg
You can pop bubbles without an egg by jumping or bumping it.
Unlock the Black Yoshi or White Yoshi by finding their eggs. Then, use the Black or White Yoshi in a stage and get a Super Happy Fruit. While Super Happy, Yoshi will be able to move horizontally very fast during the Flutter Jump. This makes crossing gaps a lot easier.
End the game with all Yoshis alive
Enter a level in story mode, then select a block 1-4. As soon as you enter, turn it off then back on. Note: This might not work with black or white Yoshis.
In the Poochy and Nippy stage, go to the location where all of the birds with the bombs are found. Get seven melons or get a heart and it will start snowing.
When you are in a level with boxes apart from each other, you can push one of them to another one and they should vanish. You should then get a melon. Some boxes are not always moveable -- try to push it first to find out.
Melon instead of heart
If you eat only melons, at the end a melon will appear instead of a heart.
Collect six melons in a row during a mini-game to get a heart fruit. Eat the fruit to create a letter made from coins at the end of the mini-game. If you use the letters in the order of appearance by level, they spell the following phrase: "YOU ARE YOSHI'S GREAT PARTNER".
Adjust stage select display
Press (C-Left) or (C-Right) to turn the display, or press (R) or (Z] to adjust the zoom.
Select Yoshi's color in practice mode
Select any course under "Trial" mode. Select the desired Yoshi and press (Start), then press (Start) + (Z]. Press (B) and being practice mode with that color Yoshi.
Press (Z] + (L) + (A) + (B).