From Kirbypedia

Sometimes when Kirby isn't traveling and fighting enemies, he likes to play a variety of fun bonus games. Some are hard, others are easy, some are multi player, while some are only for one.

Some bonus games can be accessed at any time, others are only available under specific circumstances. Many times they offer extra points or extra lives for winning.

Alphabetically

100-Yard Hop

Air Glider

Air Grind

Air Hockey

Arena (Adventure)

Block Attack

Bomb Rally

Boss Endurance (aka "Boss Butch")

Bumper Crop Bump

Burst-a-Balloon

Cart Run

Checker Board Chase

Chicken Race

Crackity Hack

Crane Fever

Destruction Derby

Drag Race

Do the Kirby

Egg Catcher

Goal Game

Heart Star Mini-Games

High Jump

Hurdle Race

Kirby Melee

Megaton Punch

Paint Panic

Quick Draw

Roll-o-Rama

Samurai Kirby

Smash Ride

Speed Eaters

Speedy Tea Time

Star Catcher

Target Flight

Treasure Shot

Up Cloud

Up Down

VS Dedede

Wave Ride

By Game

Adventure Mini-Games
Pinball Land Mini-Games
Dream Course Mini-Games
Dream Land 2 Mini-Games
Block Ball Mini-Games
Super Star Mini-Games
Dream Land 3 Mini-Games
64 The Crystal Shards Mini-Games
Tilt 'n' Tumble Mini-Games
Nightmare in Dream Land Mini-Games
Air Ride Mini-Games
Amazing Mirror Mini-Games
Canvas Curse Mini-Games
Squeak Squad Mini-Games