Because some teachers to supervise students at camp. Must be provided to teach instead. It might be some difficulties with regard to the continuation of the course of study.
Because some of the teachers who want to take care of the students at camp, it must have been provided to teach instead, it might be some jam with regard to continuity of learning subjects.
Some people have to go to school because students at the camp, it shall be provided to teach instead of so there may be some delays on the continuity of subject.