Bubble Bowl
If you have enough golden spatulas than go to where it shows a crossing sign that will not let you get in. It will open and you have to fight Sandy. Beat her and you will get prizes. One of them is Bubble Bowl.
1,000 shiny objects
Pause game play, then hold L + R and press Y, X(2), Y(2), X(2), Y.
Concept art
Go to the third part of Bikini Bottom. Get 40,000 shiny objects. Go to the movie theater and press R to go inside. Press A to see the art.
Sand Mountain: Golden Spatula
At Sand Mountain, fall and die when you are sliding and time should run out. You will get the Golden Spatula.
Entering The Salty Spittoon
Destroy Weenie Hut with the Aquaglove to gain entrance to the Salty Spitoon. Everyone inside is a Boss; just battle them.
Secret sock in Squidward's house
Go into Squidward's Tiki and destroy the moose statue above his fireplace. The camera will turn to the window, and the sock will appear for Patrick.
Underwear and Golden Spatulas
The first pairs of underwear can be found on top of SpongeBob and Squidward's house. Hit the buttons between SpongeBob and Squidward's house and Patrick and Squidward's house. Get on Patrick's house and jump on the moving platform. Get the underwear on Squidward's house and jump on the following platforms to Spongebob's house. The spatula is there.