Allowing low-income students to use tuition vouchers to attend private schools will not damage public schools - even if the vouchers also go to low-income students already in private schools. That is the conclusion of a quantitative and qualitative study of school choice plans proposed for Texas schools. The findings in Texas probably apply equally in other states.

The study evaluated a proposal to supply tuition vouchers worth 80 percent of the state's per student cost of education to low-income students wishing to go to private schools. The public school in the student's district would retain the remaining 20 percent. The evaluation found:

• On the average, the variable cost to a public school of an individual student is 87 to 93 percent of operating expenses, so with few exceptions (such as in very small districts) the revenue loss for public schools would be less than their reduction in costs.

• Concerns that only the least-expensive-to-educate students would move to private schools have not been borne out in existing experiments with choice.

• The cost of giving vouchers to low-income students already in private schools would be less than 1 percent of current public school spending.

Can the private sector accommodate all the students who opt out of the public schools? That depends largely on the willingness and ability of individuals and groups to start new schools or expand existing schools in response to buying power represented by the vouchers. The study found:

• A voucher for 80 percent of the public school cost should be lucrative enough to encourage private school expansion.

• However, there might be hesitation to start or expand a private school because the voucher programs are viewed as experimental and subject to rescinding by legislation.

Transportation would not be a major stumbling block if participating private schools provided the same services as public magnet schools - transporting students from a limited number of stops, usually the public schools they would have attended. Students could get to these transfer points via the public school bus system.

Given an option, would parents choose schools for academic quality or for other reasons?

• Low-income parents in privately subsidized voucher programs in Texas cited academic quality and discipline/safety as the most important reasons for taking their children out of public schools.

• Parents in similar programs in Milwaukee and Indianapolis rated academic quality as the most important reason they enrolled their children in private schools, with discipline in the chosen school also high on the list of reasons.

Source: J. Chrys Dougherty and Stephen L. Becker, "An Analysis of Public-Private School Choice in Texas," February 1995, Texas Public Policy Foundation, 8122 Datapoint Drive, Suite 300, San Antonio, TX 78229, (210) 614-0080; and National Center for Policy Analysis, 12770 Coit Rd., Suite 800, Dallas, TX 75251, (972) 386-6272.