Here is the full list of all 26 Putty Pals achievements.
Finish story mode
Do 100 trampolines
Complete world 1
Complete world 2
Create 10 bridges
Create 20 platforms
Bounce on 100 mushrooms
Complete a world without dying
Complete 1.10 without touching lava
Plant 150 flags
Collect all 3 collectables in a level
Collect bronze in all time trials
Collect silver in all time trials
Collect gold in all time trials
As yellow putty, trampoline at the end screen with a thumbs up
Collect all world 1 collectables
Collect all world 2 collectables
Swing straight into a cup from a swingbox
Stick to 100 walls
Do a fist bump
Create 20 boxes
Lose a collectible and get it back again
Complete World 3
Collect all the collectibles in world 3
Sink in quicksand with a thumbs up
Bring the coconut with you