The highest possible score in bowling is a 300 game. That is achieved when a bowler rolls 12 consecutive strikes in a single game.
A game consists of 10 frames. A frame consists of two attempts to knock down all the pins. If a bowler knocks down all 10 pins on the first try it is called a strike. If a bowler knocks down all the pins with two deliveries in a frame, it is called a spare. If the bowler fails to knock down all the pins within a frame, it is called an open frame.
A spare counts as 10 pins plus the pins knocked down on the next delivery.
A strike counts as 10 pins plus the pins knocked down on the next two deliveries.
Below is an example of a game of bowling. Click on the frame tabs for a frame by frame explanation of how the game is scored.