Fire administrators, hire teachers.
One great example from last year was when the school was facing budget cuts after a bond failed. Rather than cut any teachers or staff, she was able get a massive PTO fundraising effort to bring in tens of thousands from the local community. She also worked with local businesses to donate thousands of dollars worth of paper, office and maintenance supplies, and even food for some of the fundraising events.
Getting rid of the "overhead" is a cop-out. With fewer (administrative) people, you're going to get less administration done - people aren't going to magically do more work. If you can pinpoint those tasks that are relatively unnecessary, you're got a real contribution to make. However, that's often surprisingly tricky, which is why in all kinds of cost-cutting debates people pretend theres this "overhead" that's nicely pre-categorized and ready to cut.
If only it really were that simple.
The laughable part is that the goals that the administration pursues are, at best, tangential to the goals that everyone else has for school systems.
They want their children to have an adequate education... but the principal made sure no one was laid off, and that morale was good among the employees.
But today, that number is much higher. Mainly because of increased reporting requirements (No Child Left Behind, etc). But also to do things like write grant proposals (the federal Department of Education hadn't been created in my time, and wasn't handing out money)