Listed below is where each Icon is located and which game it unlocks.

Unlockable	How to Unlock
Aeronauts	Secret room located in level 4
Apple Masher	Secret Room on top of the heystacks in level 3
Bale Out	Secret Room in Zuckerman's Barn
Bounce	Enter the hole in the tree and search in the branches in level 8
Bumper Cars	Ledge outside of the circus tent in level 13
Food Catch	Enter the tires and the icon will be on the tire pile in level 10
Ring Toss	Secret Room outside of the circus tent in level 14
Snacktime for Templeton	Enter the tires and the icon will be on the tire pile in level 9
Spree Ball	Ontop of the Information Booth in level 14
Water Fun	Enter the hole in the tree and search the branches in level 5
Webbing Crashers	Secret room next to the water wheel in level 6