Mini-games can be found in rooms in world map for the various levels. They can only be visited once.
Crane Fever
The crane game gives you to chances to collect pink kirby dolls. To get them, hold 
until the crane is directly above the doll, release , and press and hold again until the claw is on top of the doll. Collecting a small doll gives a 1-up, while getting a large doll gives 2 extra lives.
The catch for the large dolls is that they are harder to collect; they sometimes drop out of the crane on the trip back.
Egg Catcher
Eat all of the eggs thrown at you, but avoid eating the bombs. As you eat eggs, the meter on the left fills, but eating a bomb ends the mini-game.
Quick Draw
Press when the enemy draws his pistol. If you are too slow, the enemy will knock you out, ending the mini-game.
The bonus is awarded based on the number of levels you pass. If King Dedede hits you, you will get a 1-up.