I would expect your administration to fix this situation within a few days.
If not, you do have to refuse to accept 43 students in one studio art
class because it would be very unprofessional.
Some rationale to not have .
1. Quality of instruction will suffer.
2. Complaints from parents are likely (this is powerful with administrators).
3. Students will complain to you and you will be forced to send them to
4. Teacher burnout - plus nobody else would take the job if the word gets
5. Behavior problems including fights can be expected.
6. Inadequate space for working and for project storage.
7. Not enough supplies.
I might tell the class that this is a temporary problem until the
administration solves it. Then I would go on to explain to the students
that they will have only videos (tested), reading, writing, assignments
about art and art history until the situation is fixed. No art studio
activities until the situation is fixed.