The following are known Action Replay Codes for Mario Kart: Super Circuit on Nintendo Game Boy Advance (GBA).
These codes were also known as GameShark Codes and in most cases will work on both devices.

These codes are for the U.S. version of the game.

Master Code – Must Be On
c0a18c4f
0c8f71a3
295d0574
8cec4fab

Infinite Retries
db06cf50
a3c2b299

Infinite: Stars
9c0d4f6e
9cc1c9a5
13df2c72
e344b903

Infinite: Mushrooms
314c72c1
cde33061
13df2c72
e344b903

Infinite: Lightning
ad1d9fb9
6e7151e8
13df2c72
e344b903

Infinite: Boos
233b6a8f
8bc62a04
13df2c72
e344b903

Infinite: Bananas
e6b9d322
3de06aeb
13df2c72
e344b903

Infinite: Red Shells
e97e51d6
dfba334c
13df2c72
e344b903

Infinite: Green Shells
86234ee1
6f82ae8c
13df2c72
e344b903

Infinite: Tri-Red Shells
ab4fd3ac
d2953546
13df2c72
e344b903

Infinite: Tri-Green Shells
927cb7fe
c729d099
13df2c72
e344b903

Infinite: Spiny Shells
7577429e
fac37a58
13df2c72
e344b903

Infinite: Tri-Mushrooms
8056a420
dbb4d620

Infinite: Tri-Mushrooms
13df2c72
e344b903

Have 99 coins
19a46b0a
ac11d523

Press AR Button: Slow
dbba3a89
4cb74b94