Instructions
Follow the storyline throughout the game in order to continue unlocking skate parks. Complete the goals for each park so that you can advance in the game. Also, make sure to do well in each competition to bring your rank up.
Get to rank 35 while playing through the storyline. You may need to go back to different competitions to get to this ranking. For example, if you got second place in one of the first competitions go back and get first place to bring up your rank.
Ride up the big hill in the city and find the reporter with the camera crew. Press your "A" button to talk to the reporter. The reporter will then give you a few tasks which you must complete.
Complete all of the tasks offered by the reporter and the Fun Park level will be unlocked. Some of the tasks include grinding around the entire park and collecting all of the letters in the word "skate."
Press your start button and click on the option to view your map. You will see that the Fun Park is now available. Remember the location and skate to play new challenges in the Fun Park.