The application offers to work on adding and removing items to a collection.

Elements (fruits, vegetables...) are on a plate. The monster wants a different amount, indicated above the plate. The child must therefore add or remove elements to obtain the desired quantity.

*Level 1 :
The monster wants a quantity (here 9).
The child must press the arrows as many times as necessary to add or remove items from the plate.

*Level 2 :
The monster wants a quantity (here 5).
The child must indicate the number of elements to add or remove with the side buttons. The result is displayed in real time, before validation.

*Level 3:
Like level 2, but the result is not displayed before the validation of the student.

*Representation of numbers:
The child can change the representation of numbers by clicking on the "Serge" button in each level.

*Options:
From the home menu, click the option button to set the work interval.

* Scores:
Each part offers 5 questions. A correct answer wins:
- 1 star on the first attempt,
- 1/2 star on the second attempt.
Only the best score of each level is kept.
To reset the scores, click 5 times on Serge the llama on the home screen.