Set a school or office stationery budget.
Stationery is bought per person, so the useful unit is a per-person kit: notebooks priced by count, plus a single allowance for pens, folders and the rest. Multiplying by the number of people gives the budget, and the notebook share shows whether paper is quietly dominating the list — which is usually where bulk buying pays off most.
Stationery kit cost
Cost per person = notebooks each x notebook price + other supplies; total = cost per person x people
Attack the largest share first. If notebooks dominate, multipacks and generic brands cut it fastest; if the other-supplies allowance dominates, reuse last year's folders and cases.
Buy consumables early when promotions run, but hold back items the school may specify later. Duplicate purchases are the most common waste in back-to-school budgets.
Yes — treat staff as the people count and the other-supplies allowance as the per-desk kit.