After a week, we went back to school to get our boxes, since they take a long time to print. They were as we had imagined, except for one detail : the 3D printer had a large margin of error : we had not paid attention to this detail...

This clearly shows the limits of 3D printing : printing even a small box takes a considerable amount of time.
Using the laser cutter could have been another solution, however, the boxes wouldn't have been as resistant since the thickness of the wood is very thin.
The advantage of using the 3D printer was the possibility of adding layers to make it thicker.
The boxes are therefore not very thick, but strong enough to handle repeated punches.