Spongebob Squarepants: 

    Revenge of the Flying Dutchman 

  
Gamecube


  





Unlock Fishing Gear:

  In Bikini Bottom, body slam the button near The Krusty Krab. Then, go into the 
  changing tent and press A. 

  

  Unlock Mermaid Man:

  At the Downtown Construction site, talk to Patrick and give him a bag of Krabby 
  Patties. Then go into the changing tent and press the X button. 

  

  Unlock Reef Blower:

  Enter the Jellyfish competition in Jellyfish Fields and catch 100 Jellyfish 
  and bring them back. Then go into the changing tent and press the Y button.

  

  Jellyfish Fields Bus Ticket:

  After Patrick leaves the Chum Bucket in search of Plankton, go to Resident Row. 
  When you're there, search the buildings near Patrick's rock. There will be a 
  Pink Jellyfish circling one of the buildings. Floating underneath it is the 
  Jellyfish Fields Bus ticket. Either catch the Jellyfish or jump up to reach 
  it. The Jellyfish Fields Bus Stop is in front of Spongebob's pineapple. 

  

  Chum World Bus Ticket/Pass:

  In Jellyfish Fields, find Plankton. He will not give you the ticket, but he 
  will tell you to go find one of the Chum World clown. When you find him, you 
  will make a deal with him. But first you must defeat him. When you do, he will 
  bounce away and give you the Chum World pass. 
Downtown Bus Ticket:

  After you find the first treasure, go see Squidward. He will race you to the 
  Krusty Krab. Once you're there, Mr. Krabs will tell you he will shut down the 
  Krusty Krab. When you cheer up Mr. Krabs, he will tell you to meet him downtown. 
  Then he will give you the Downtown Bus Ticket. The Downtown Bus Stop is near 
  the Krusty Krab and the Chum Bucket. 
Goo Lagoon Bus Ticket:

  After you find the Treasure in Jellyfish Fields, go to the Goo Lagoon Bus Stop 
  located in Resident Row. You will see Larry the Lobster in a belt. Talk to him 
  and he has an extra Bus Ticket. He will give it to you if you give him 50 Jellyfish. 
  The bench is in Resident Row.
Sandy's Tree Dome:

  After you deliver Krabby Patties Downtown, follow Patrick to Resident Row. Patrick 
  will not be there, but Squidward will be having a yard sale.You have to talk 
  to Squidward first. Walk away from Squidward and the narrator says to sneak 
  up on Squidward to borrow a book from him. After you read it Sandy will knock 
  the rocks out of the way. Before you go into the Tree Dome you will have to 
  challenge Sandy to a Karate test. Then buy Sandy a gift from Squidward's yard 
  sale and you will unlock the Tree Dome.
Dutchman's Graveyard:

  Before you find all 7 treasures, karate chop the barrel at the back door of 
  your pineapple. When you find all 7 treasures, the Flying Dutchman will drop 
  cargo on your pineapple. The front door will be blocked, so you have to go out 
  the back door.When you're outside there will be a cannon next to you. Jump into 
  the cannon and press the action button. Then you will be in the Dutchman's Graveyard. 
  

  

  

Thanks to Revolution readers Springboob Squirepin/Master Fancyson/Clown's frown 
  and Goo Bafoon!