Often we hear school administrators say, "I treat the district's money like it was my own". That is exactly the wrong thing to do and it tends to get us in trouble. By taking the position we take ownership over someone else's children and assets. And when we do that we tend to substitute our judgment for theirs. "After all we have experience in these matters and we know a mistake when we see one"!
A board has the right to spend district money how it sees fit, even of frivolous things, as long as it is not illegal. You can and should offer your advice, but you should never buck or attempt to "work around" the decision, regardless of how foolish you think it is.
You don't have the right to tell your next door neighbor to sell his bass boat and put the money in his kids' college fund. And you don't have the right to tell the board how to spend its money.