This usage of set is a new one one me. The meaning can be guessed at, but is it in common use in AE/BE?
Additionally, does it work for you if I say, "setting class such a ...." instead of the class?
We can use 'class' as a form of address with no article; we can say 'in class' (= during the lesson/period), but when we use 'class' to refer to the group of learners as a whole, we use articles as we do with any other noun.