Cal & Bomba is an award winning math game designed by the Norwegian game studio Filiokus. The player has to program small sequences of instruction that combine percentage calculations with other game mechanics to solve puzzles. The game is designed to let players visually experience the consequences of mathematical choices.

As a teacher you should get acquainted with the game. How the basic gameplay works, what the different enemies do and what tools are at your disposal. If the students have questions, it is nice if you have the answer.

Students can play individually or in pairs. Let them start by playing the prologue. After that the students can choose if they want to play in normal or hard mode. 1 hour to 90 minutes is often a fine length for a session. In this time your main job as the teacher is to observe. Look for students who normally struggle in math class, and who seem to be doing better than expected. It is our hope that you will find them, and be surprised by their level of focus, accomplishment and joy. You will also probably find that different students have different play styles. Some students will be calculating and thinking strategically, others will be guessing wildly. Try to see if the ones that are guessing are gradually getting more precise in their guesses. And ask them to explain their choices. 

Talk about the mathematical theory behind the game. Go through these questions and solve them together using the mathematical language. 

A - What happens if you increase a value by 100% and then decrease it by 50%?

B - What is the difference between increasing a value by 100% two times, and increasing a value by 200% one time?

C - What happens if you increase a value by 50%, and then decrease it with 33,33%?

D - How can an increase of 20% followed by an increase of 66,67% be equal to one increase by 100%?