Here is the full list of all 43 SpongeBob's Truth or Square achievements worth 1,000 gamerscore.
You completed a level without dying, without invincibility.
You upgraded all of SpongeBob's furniture.
You unlocked all of the available costumes.
You collected 99 Lives.
You found all of SpongeBob's Happiness Objects.
You found the Picnic Basket.
You found Patrick sleeping in all levels.
You found the Volcano Hot Sauce.
You unlocked all concept art.
You survived all 7 Task Tiki Combat Challenges.
You found Mr. Krabs' 1st Dollar.
You found Patrick's Alarm Clock.
You fed Patrick a kelp hot dog.
You found Mermaidman & Barnacleboy's Ring Box.
You found Mermaidman's Utility Belt.
You found the Bellybutton Lint Earmuffs.
You found Squidward's Paints.
You found Snellie's Pet Carrier.
You found the #1 Soda Drinkin' Hat.
A Co-op buddy, as Plankton, made 100 Happiness Nuggets sad.
You found the Heart-Shaped Acorn.
A Co-op buddy, as Plankton, defeated 100 enemies.
A Co-op buddy, as Plankton, shook 50 enemies.
You found the Magic Conch Shell.
You found the Bubble Wand.
You defeated 30 enemies in a row while buff.
You found the Baby Jellyfish.
You watched all of the credits.
You completed the game.
You found the Karate Gloves.
You collected 10,000 Happiness Nuggets.
You found the Open 24 Hours sign.
You broke 1000 Plankton Tikis.
You found the Krabby Patty.
You made SpongeBob grow old.
You found the Aquaphone.
You broke 150 Squidward Stone Tikis.
You defeated 250 enemies with SpongeBob.
You found the Toy Clarinet.
You found the Golden Spatula.
You found the Hot Dog.
You found Sandy's Iced Tea Glass.
You found SpongeBob's Jellyfishing Net.