Because then they are quiet, even if I ask them something. In the B-shirt - even though I taught less there - it was much easier to pull the reaction out of the children. (It is also interesting that they did not protest in the B-side when I started to connect the material with English. They squirted in the A-class.)
(It is also interesting that they did not protest in the B-side when I started to link the material to English.