With that said, maybe have someone you respect take a look at your resume. See if it can be tweaked so that it might catch an eye. HIGHLIGHT teaching experiences and success in the classroom. Limit college experiences to the bare minimum. Consider creating an online teaching portfolio - include recordings of ensembles (even snippets are good), lesson plans, exercises, C&SR evaluation sheets (both the good and the bad), videos of you teaching (fundamentals, rhythm, sight reading - are always great to see). It may seem like alot of work, however- when the person deciding who to interview looks at a resume that is well done, and then they can click on a portfolio that is well presented - that person will get an interview over someone who just sends a resume.
Also- please include your principal and your head director in your references. They are going to get a call anyway. I truly wish you the best.