Calif. Public, Private School Pupils' Scores Found Equal
Davis, Calif--When matched for background factors and ability, California's public-school students hold their own with private-school students in reading and mathematics, according to a recent study by a researcher here at the University of California.
Julius M. Sassenrath, chairman of the university's education department, found almost no difference between the achievement scores of 49 high-school seniors in public schools and 49 comparable pupils in private schools on the mathematics and reading sections of the Stanford Test of Academic Skills.
All 98 students took the test in 1982, before graduating from high school.
The achievement-test data "led us to the conclusion that private and public schooling has, on the average, about the same influence on academic achievement in reading and mathematics," Mr. Sassenrath said.
"Even though private schools can be more selective in their choice of students, private- and public-school students are doing equally well when matched on ability and socioeconomic status--which means the public schools are doing something right," the researcher noted.
For both groups, the average raw score in reading was 33.10 out of a possible 50--equivalent, Mr. Sassenrath said, to about an 11.5 grade level.
The private-school students scored marginally higher in math, with 30.12, compared with the public-school students' average score of 30.10.
Mr. Sassenrath had matched the groups according to scores on intelligence tests, socioeconomic status, ethnic background, gender, and age. Each group included 30 whites, 10 Hispanics and nine blacks, and each group had 24 females and 25 males.
The students were drawn from a sample of 1,500 students that he began surveying in 1972 to determine whether standardized tests were equally reliable for students from different ethnic backgrounds.
Mr. Sassenrath learned in 1982 that 49 of the original students went on to private schools. He decided to match them with 49 similar public-school students and compare their academic success.
Students in the private-school group were attending 47 schools in California--75 percent of them church-affiliated. The public-school students also were enrolled in 47 schools in the state.
Of the private-school students, some had been enrolled in their schools for as long as 10 years and none for less than two years, Mr. Sassenrath said.
"The average time was five-and-a-half years," he said. "We figured that if kids had been in private schools for five-and-a-half years, if there were going to be any beneficial effects, it should happen in that time." Mr. Sassenrath acknowledged that "it would have been nice if there had been a larger sample for the study.
But since we matched the students so closely, even though the sample was somewhat on the small side, that's not debilitating," he said.
The findings may have public-policy implications as well, according to Mr. Sassenrath.
"The study indicates any political decision on the issue of educational vouchers or tax credits for students attending private schools should be based on financial and legal reasons and not on the claim that private schools necessarily lead to higher scholastic achievement," he said.