...Nothing to say...
collect a purple orb
Beat Level 4
Beat Level 3
Beat Level 2
Beat Level 1
Collect $3000 in a single flight.
Escape from a stall at less than 3m altitude.
Bounce along for another 100m after making contact with the ground.
Collect all the available types of stars in a single flight.
Collect 30 space stars in a single flight.