Here is the full list of all 13 Classic Pool achievements worth 1,000 gamerscore.
Unlock all available achievements in the game
Play your first match in single-player mode
Play your first game in multiplayer mode
Win your first match in single-player mode
Win your first match in multiplayer mode
Win a match with second opponent in single-player mode
Win a match with third opponent in single-player mode
Win a match with fourth opponent in single-player mode
Win a match with fifth opponent in single-player mode
Win a match against each of the opponents
Unlock all available cues in the game
Unlock all available billiard tables
Win 5 matches in a row in single-player mode