I'd say that charitable donations for specialized labs and programs are acceptable as long as there is a clearly defined caveat that the donor gains no advantage of any sort other than honorable mention and an appropriate tax deduction. Many school districts are under extremely restrictive budgets and can't afford ancillary programs. For instance, my clinic provided a local high school with sufficient funding to construct and equip a pre-nursing medical sciences lab for the specific purpose of interesting and preparing students for entry into post high school medical education programs. We received nothing in return other than a brief ceremony celebrating the opening and our clinics name as part of labs name.