The reality is, as long as you have football -- and wildly overpay for its coaches -- you will have a fundamental imbalance in expenditure BY GENDER in high school sports. Unlike college sports, where you can (somewhat) address fairness/opportunity issues through grants-in-aid, it's much tougher to do at the high school level.
The way to begin is by assuring that boys' and girls' programs in similar sports have equal budgets and access to resources: i.e., boys' and girls' soccer, basketball, baseball/softball, lacrosse, swimming, track and field, cross country, etc. Address overall inequity by funding traditionally "girls" sports -- such as volleyball and cheerleading -- at levels "comparable" to other sports, on as per participant basis.
As far as football is concerned, take a long, hard look at trimming back bloated coaching staffs and salaries, and restricting roster sizes to more reasonable numbers.
There is absolutely no reason to pay a football coach six figures -- not when most would do the job for less. Similarly,there's absolutely no reason to carry more than 100 kids on varsity and jayvee football combined. Just as there is absolutely no reason for Wando to carry 30-plus on its varsity soccer roster,
By the way, I'd have absolutely no problem eliminating ALL extracurricular activities from American public schools, but as there is no way this will happen, I simply advocate rational and fair expenditure and allotment of resources. The days of every Driver Ed teacher being a football assistant must end, just as hiring a football assistant to fill EVERY PE opening must end.