A few rigorous studies have examined the relationship between being offered school vouchers and academic outcomes. Early evidence from experimental research on vouchers has shown them to have mixed effectiveness in increasing achievement among the students who receive them in comparison to those who do not. Howell, Wolf, Peterson, and Campbell (2000) examined the impact of offering privately-funded vouchers to parents in Washington, DC, Dayton, OH and New York City that they could use toward tuition for their children to attend private schools. In their experimental evaluation, academic outcomes were analyzed for students who were randomly assigned to a group that was offered vouchers or another group that was not offered vouchers. Achievement outcomes for students in the Washington, D.C. program only as children in that city were in grades 2-8 at the baseline and some subgroup analyses were done for children in grades 6-8 and were presented in the report. Of the students who were offered vouchers, 53 percent used them to attend private school by the end of the program's first year. The study suffered from attrition problems, with the follow-up response rate of 50.3 percent; however, there were no statistical differences between response rates of those who were offered vouchers and the control group. The study found that among African Americans, the program had mixed, but more positive, achievement effects. In the first year after being offered vouchers, the overall achievement of 6th through 8th grade African Americans who were offered vouchers decreased by 8.8 percentile points. In other words, they trailed control group students who were not offered vouchers by 8.8 percentile points based on their combined reading and test scores. There was a decrease of 19 percentile points in reading, but there was no difference between the two groups math achievement, but there. In the second year, however, African Americans students receiving vouchers had scores that were 10.3 percentile points higher than African American students in the control group in overall combined achievement test performance, and they had scores that were 12.8 percentile points higher than control group students in math. No significant differences were found between the groups in reading by the second year evaluation. However, for adolescents of all other racial and ethnic backgrounds, vouchers had no impact on academic achievement outcomes, as indicated by math and reading or overall combined test scores (Howell et al., 2000). The effectiveness of privately funded vouchers, as demonstrated by early evidence from this study, is mixed for children of different racial and ethnic background, and appears to be somewhat positive in the longer run for African Americans who receive them.

Similar results were found in an experimental evaluation of a voucher program in New York City that looked at the effect of vouchers on the achievement of 3rd through 6th grade students who received vouchers to attend private schools (Myers, Peterson, Mayer, Chou, and Howell, 2000). 76 percent of the students who were offered school vouchers used them when offered, and 64 percent were using them two years later. Selection bias may also enter as a limitation given that a substantial number of students who were offered vouchers did not use them. However, the researchers tried to control for these selection factors in separate analyses and reported that their results were not biased significantly. This evaluation suffered from a moderately high level of attrition in the sample over time, with a 65 percent response rate in the most recent follow-up interview. The study showed that there were no overall differences between test performance of the scholarship group and the control group by the second-year follow-up. However, subgroup analyses showed that significant differences occurred among African American 6th grade students. Specifically, the researchers found that 6th grade students who had been offered school vouchers scored 7.92 national percentile ranking points in their combined math and reading higher than the control group students who were not offered vouchers. Similar differences were found in reading and math performance among African Americans based on their scholarship status.

While these two evaluations show some evidence of the effectiveness of vouchers for improving the scores of young adolescents African Americans to higher levels than they would be in their absence, it is important to note that these studies only looked at one aspect of vouchers. These studies were designed to examine differences between students based on whether they were offered school vouchers. For instance, this study did not examine the effects of vouchers, or publicly funded school vouchers, in particular, on the public school system and on public school students' learning. It is not apparent if vouchers affect public school student performance positively or negatively. For example, some argue that competition and reduced class size results from students being offered vouchers and public schools respond by running more efficiently, thereby increasing scores for students offered vouchers and those not offered vouchers. Others believe that high achieving, highly motivated students from higher SES backgrounds (who seem to gain the least from the vouchers, after controlling for preexisting differences) will be more likely to have parents that seek out and attain vouchers; they are concerned that vouchers will lead to a change in composition and decreased school funding that will harm the school and its ability to create high performing students. Further, the larger school choice reform movement, which includes the establishment of charter schools, has not been rigorously evaluated thus far. More research is needed to decisively state the impact of vouchers and other school choice education reform efforts on academic outcomes of adolescents.