Since you asked, forget the tie. Get the dress shirt (white) and navy jacket. Wear the grey Dockers, of khakis. More bang for your buck, and dressy enough to not be ignored at a public meeting. Ties are becoming less and less important it seems, outside of a courthouse.
As for the statement, stick to a results based argument. Look at the test results, which explain why the schools are worth funding.
In my experience fighting with the school board and superintendent, test results are all that matters what gets their attention..