Here is the full list of all 48 Toejam and Earl: Back in the Groove! achievements worth 1,000 gamerscore.
Complete a random world game
Hit and leave through the very first exit in the Hyper Funk Zone
Collect a locked present
Make other player snap out of being in love by slapping them
Make other player wake up by shouting at them
Hi Five another player 3 times in one game
Play as both old Skool TJ and as Old Skool Earl
Get a game over before level 3
Get hit by Cupid's arrow 5 times in one game
Complete a fixed world game
Visit a backer character
Go for a ride in the Evil Elevator twice in one game
Open the Major Randomizer or Baby Randomizer 3 times in one game
Fall off current level 5 times in one game
Eat every type of food in the game in a single play through
Open unidentified presents 15 or more times in one game
Hide in sunflowers 4 times in a game when being chased by an Earthling
Get to hot tub island
Open the Total Bummer twice in one game
Send an identified bad present to another player
Use Heal Friend Present on another player 10 times in one game
Use The Boom Box 4 times
Give a life to another player 3 times in one game
Uncover all the map tiles for at least 5 levels within one game
Complete a game with a friend (local or online)
Get to secret Funkotron Level via a secret doorway
Play as each of the playable characters
Beat the 5th level in Rhythm Matching
Have 99 bucks
Successfully open 10 broken presents in one game
Have 10 broken presents blow up on you in one game
Pop 8 or more Earthlings who are dancing at a boombox in one game
Pop a mole who has stolen one or more of your presents
Save yourself from burning up by jumping in water
Catch Santa 3 times in one game
Catch 5 elves in one game
Get killed by a Little Girl with a Teddy
Unlock all power hats
Collect all of the locked presents
Complete hard world
Reach the end of the HyperFunk Zone
Pop at least one of every bad Earthling type in one game
Beat normal or hard world without dying
Beat normal or hard world without popping a single Earthling
Open an unidentified Major Randomizer, Total Bummer, or Instant Demotion after level 20
Beat normal or hard world without opening a single present
Visit every backer character
Reach the rank of FunkLord