If I would have written that letter, it would have been worded more factually. Something like,
Dear Parent,
Thank you for supporting Proposition 100, the one cent sales tax increase that went primarily to support Arizona schools. Despite the fact that we were the beneficiary of one of the largest sales tax increases in Arizona history, we are still unable to provide for the basic needs of students, i.e., transportation to and from school. We find it easy to base our incompetence on the budget despite the fact that our economic situation has impacted every business and individual in the community. Somehow we thought we were immune.