Treasure Trail

The Treasure Trail is a path you can take after you get A's in all your classes. There is no time limit, despite what the game implies when you first enter. You can get 120 pearls, and you keep a trail behind you afterwards for a few minutes. About halfway through the path, there is a treasure chest in the middle of a lake to the right that gives you 100 pearls. 
Next to that chest is a oyster that you can hop onto for another pearl. There's also a blue and yellow flower to the right beyond the oyster, which you can pick up and use later for role-plays. The blue flower gives you a blue mist and sparks, and the yellow flower gives you a golden circle aura.