Naive question: isn't the data officer basically a single point of contact on data issues (and have some general knowledge on the topic)? Why can it not be someone working at the school?
By default, if they cannot delegate, wouldn't the responsibility go to the director of the school?
I feel like we tend to be overly pedantic in how we interpret some of the GDPR. For example, a small shop might not have a physical security officer. The owner/manager of the shop still has to have some general sense about ensuring the physical security of the shop, dealing with contractors/vendors (alarm system), etc.
With data collection, isn't it the same? Aren't people already doing this? No one would collect data, and not care about its basic security?
I think it's great that GDPR is forcing people to wonder: what data do we have, is it shared, who is responsible, what's the retention, and can it be deleted on request. After that, I don't buy into the fear mongers trying to make a quick buck.