On the Waco Trib's editorial there is an editorial on school choice. The article says that one of the drawbacks of school vouchers would be that they would reduce the funding of public schools. Really?
According to the Texas Education Agency, the average per pupil spending in Texas public schools in 2004-05 was $9,269. House Bill 18, which is a bill that would create school vouchers for certain children states that the voucher value would be "equal to the total average per student funding amount in the school district the child would otherwise attend during the preceding school year for maintenance and operations, including state and local funding, but excluding money from the available school fund." Now if this bill were to pass, the revenue question would be a wash for schools. They would lose 1 student and the funding associated with that student. The school district and system as a whole would be no better or worse off financially.
Most voucher proposals call for a voucher amount that is less than the average per pupil spending in public schools. In this case, the public school system would actually be better off financially from the voucher program. They would lose one student, but the revenue decrease would be less than the per pupil spending. There would actually be more money in the public system, assuming the voucher holding student goes to a private school, under a a voucher system in which the voucher amount is less than per pupil spending.
Whether or not school vouchers will be beneficial or are a good idea is a seperate question. However, the idea that school vouchers will reduce available public school revenue as a whole is a myth.