At the level selection screen, hold Select and press L(2), B, A, R. A list of bonus games will appear. If you win the selected game you will get a prize.
Successfully complete the game to unlock an extra level for each world. Finish all eight levels in each world with a 100% completion to unlock a ninth level in each world.
Get 1,000 points in a world (100 points on all ten levels including Extra and Secret levels). A star will appear on the game selection screen. Get five stars on that screen to unlock hard mode.
Successfully complete the game in hard mode.
Get your total points for a world to equal exactly 777, to get 7 extra lives.
To get special Yoshi eggs with out having to find special boxes, fire a Yoshi egg in an area that will cause the egg to bounce off the walls and back to you. When the egg returns to you, quickly use Yoshis tongue at the egg. If successful, you should have a special Yoshi egg.
Press any direction on the D-pad and the target will stay up.
When you arrive in the Boss room where that small plant is located, step on the first block on the platform, then shoot a egg at him. However, do not go further than the first block on the platform or Kamek will appear and turn that small plant to a huge monster.
Grab a Melon Bug (the creature that rolls up into a ball) and go to the pipe with Shy Guys jumping out of it. Spit the Melon Bug close to the pipe on the left-hand side. When Shy Guys jump out, after a while you will get a "1-Up" for each time a Shy Guy hits the Melon Bug when it is in its melon form.
Pick up the shell at the start of the level and throw it at the row of Koopas. Quit level and repeat for endless lives. Also in level 2 (the one with the ten red Koopas at the start). you can get close to thirty extra lives. When you first enter the level, hold B and run forward. You should run into a shell and will be holding it. Run back with the shell to the ten red Koopas and throw it at them. If you hit them all, you get an extra life. Get a Yoshi out of the block and run forward to the next block with a Yoshi (by the moles that pop out of the walls) and hit it. An extra life mushroom will appear. Climb the beanstalk to the clouds. To get the beanstalk, hit the block on the far left of the walls that the mole appears from. There is a Dragon (Yoshi) Coin there. Collect the other four and get another extra life. Go down one of the blue tunnels near the end of the level. There will be flying blocks. You can pick up a block and throw it at them, but an easier way is to simply jump with Yoshi then jump off in mid-air (press A while on Yoshi and R at the peak of its jump). An extra life will be in the third flying block. Leave the tunnel, then run back to the entrance. Go down the same tunnel again and hit the third block to get another extra life. Do this until you have about forty seconds remaining, then sprint to the goal with your extra lives.
Pick up a Rollie-Pollie Guy with your tounge. Do not turn him into an egg or spit him out for anyone until you get to the pipe that spits out Shy-Guys. Once there, spit the Rollie-Pollie Guy out into a 1 (square) hole on the right of the pipe. Once placed, jump onto the platform above and to the right of it. Let the Shy-Guys jump out of the pipe and onto the Rollie-Pollie Guy. Points will accumulate and will eventually give you 1-Ups continually. After a few hours, you will have 999 lives.
Immediately before completing the level, there is a bridge that bends. Get the two Red Coins, then go to the other bridge. After that go on the piece of land with a log sticking out of the ground. Stand on the edge of the log, then shoot an egg straight up. A spring ball should fall. Jump on it and you will go to a hidden stage through a pipe.
Grab a Melon Bug (the bug that curls when you approach) and take him to the Shy-Guy Pipe (where the Shy Guys appear from). Look up and shoot the bug. If done correctly, the bug should fall in the tiny space on the right side of the pipe, between it and landscape. Stand on the elevated surface and make sure you have no eggs. The Shy Guys will pop out towards you, but hit the bug. You will keep getting extra lives until you have 100. Then, get a perfect completion on World 5 and you will get the roulette game. If you get the X3; you will get 300 lives.
There is a location in the water in World 3-1 where you can go beneath a land mass to access a hidden area, by jumping off of a giant spring arrow. If you curve to the side and go above the normal hidden entrance, you should enter an area where you will be falling towards nothing. Keep going right (stay in the air as long as possible) until you reach the edge. You will be teleported to World 1-1 (and gain credit toward World 3-1) where you can gain more red coins and hearts than the maximum. It will only go to the top, but it will be 10 times easier to perfect the level.
Go up the first steep hill until you get to three pipes and a Koopa walking around. Two will have Piranha plants and one will be a Shy-Guy generator. Throw away an egg so Shy-Guys will start jumping out. Kill the two Piranha plants, eat the Koopa and stand on the pipe. Spit the Koopa shell towards the Shy-Guys. The shell will bounce between the two pipes, knocking out the Shy-Guys. As soon as ten Shy-Guys are knocked out, you will start getting a 1-Up for each consecutive Shy-Guy. The shell will keep bouncing around, killing the Shy-Guys that pop out. You can get up to 999 lives this way.
Go to a door on your left. Use a POW block or "?" and go to the door and get the secret code. This code will give you free mini-games when you go to the level selection screen.