"The Student Safety Act is about shining a light on the impact of school safety practices in the schools, on the children, on education," Ms. Lieberman said.
The Museum of Nature and Science in Dallas, however, has definitely felt the impact of school budget cuts, said Linda Murdock, the museum's director of sales.
Indeed, new research suggests that the Swedish vouchers have had a positive, albeit small, impact on student outcomes.To measure the impact of school choice on student outcomes, one has to isolate the effect of the vouchers net of other reforms.
"I like the clothes I wear because they are me," said an unnamed 12-year-old girl whose clothing preferences were cited by D. I. Jamison in a 2006 paper about the impact of school uniform policies.
To isolate the specific impact of schooling on mental skills, Dr. Lachman and her colleagues tried to control for other likely reasons one person might outshine another — differences in income, parental achievement, gender, physical activity and age.
Yet the most striking impact of school police officers so far, critics say, has been a surge in arrests or misdemeanor charges for essentially nonviolent behavior — including scuffles, truancy and cursing at teachers — that sends children into the criminal courts.
So what is the impact of school league tables?
In its earliest stages, research on the impact of school inputs was held back by the first challenge: data availability.
Controlling for student and school SES, the impact of school variables was shown to be negligible (Caponera and Losito 2011; Caponera et al. 2012).
