Banana

Spins karts that drive over it.

Triple Bananas

Three Bananas will orbit your kart.

Green Shell

Travels in a straight line and knocks over the first kart it hits.

Triple Green Shells

Three Green Shells will orbit your kart.

Red Shell

Homes in on the kart in front of you and knocks it over.

Triple Red Shells

Three Red Shells will orbit your kart.

Spiny Shell

Homes in on the lead kart and knocks it over.

Bob-omb

Explodes after a certain period of time or when a kart hits it.
Karts caught in the blast will spin or be knocked over.

Mushroom

Gives your kart a short boost.

Triple Mushrooms

Three Dash Mushrooms will orbit your kart.

Golden Mushroom

For a period of time, use a Dash Mushroom with each press of the L Button.

Bullet Bill

Transform into Bullet Bill for a while.
You will speed along the course automatically, knocking over any karts you hit.

Blooper

Shoots ink at all karts in front of you, obscuring their vision for a while.

Lightning

Lighting falls on your rivals and destroys any items they're holding.
They'll also be shrunk and slowed down for a while.

Super Star

Makes you invincible for a while.
Your speed is also increased, and any kart you hit will be knocked over.

Fire Flower

For a while, each press of the L Button throws a fireball.
Karts hit by a fireball will spin.

Boomerang Flower

Throws a boomerang up to three times.
Any karts hit will spin.

Piranha Plant

A Piranha Plant will be attached to the front of your vehicle for a while.
When it bites, your kart will also get a small boost.

Super Horn

Emits a large sonic blast to knock away nearby karts and items.

Crazy Eight

Eight items will orbit your kart. Pressing L uses the item currently in front of you.

Coin

Gives you two coins.
The more coins you have, the faster your kart becomes.