The following are known Action Replay Codes for Snowboard Kids 2 on Nintendo 64 (N64).

Device Compatibility: Action Replay & GameShark

All Gold Medals
812591300101
812591320101
812591340101
812591360101
812591380101

Infinite Left Weapons (Story Mode)
8025a6230003

Press L To Be On Lap 3 (Story Mode)
d00a1c090020
8025a6150003