Sadly, it's not just education that's suffers the "make-it-work with $0" mindset. This along the lines of "the beatings will continue until morale improves" except it's "the budget will not be funded until results are achieved." This is a management problem, not an IT problem. You need someone intelligent who speaks management to make it understood that they have to have realistic and definable IT goals which includes a willingness to fund them on your side.
I don't know much about your community but if you're lucky enough to have a grant-savvy PTO, you might be able to get them to write a grant application for the funding but, again, you need to be very clear about what the goals are and how the hardware/software you want will achieve them.
Also your local board of ed and board of finance may be interested in the dipping into the IT budget when pet project funds run low. They tend to frown on stuff like that.