Trophies - Successfully complete one of the following tasks to get a trophy:

Demolition Master (Bronze): Hit 15 objects in any single player level (original content). You must earn a bronze medal or higher in order to unlock the trophy.
Air Time Expert (Bronze): Get 75 seconds of air in any single player level (original content). You must earn a bronze medal or higher in order to unlock the trophy.
Star Collector (Bronze): Accumulate 270 stars in single player mode using your best score from each level (original content).
Trickster (Bronze): Complete 15 air tricks in any single player level (original content). You must earn a bronze medal or higher in order to unlock the trophy.
Lap Champ (Bronze): Beat all base lap times in every single player level (original content).
Race Ace (Bronze): Beat all base race times in every single player level (original content).
Smash Cars Superstar (Bronze): Get 30 stars in one single player level (original content). You must earn a bronze medal or higher in order to unlock the trophy.
Smart Driver (Silver): Find all the shortcuts in every single player level (original content). You must earn bronze medals or higher in order to unlock the trophy.
Safe Driver (Silver): Complete all single player levels without crashing or using any respawns (original content).

Additionally, there are three secret trophies:

Bronze Champion (Bronze): Earn a bronze medal, or better, in every single player level (original content).
Silver Champion (Silver): Earn a silver medal, or better, in every single player level (original content).