The game is actually 3 games in one. Try to complete them all as quickly as possible and before the time runs out! After a while a hint will pop up and then if you spend way too much time a skip button will pop up.
Your aim is to guide tadpole to his home and avoid all obstacles on the way. Hold LEFT MOUSE BUTTON to swim up, release the button to swim down. Avoid hitting Rocks, Algae and Waterbugs. Be sure to collect those bubbles, they will save you life many times.