A growing number of middle schools are requiring that students submit to drug testing, The New York Times reports. Students are being asked to provide a urine sample to participate in sports, or even in extracurricular activities such as choir and drama.

Some parents and civil liberties advocates are objecting to the tests, the article notes.

Middle schools that conduct drug tests are located in states including Alabama, Arkansas, Florida, Missouri, New Jersey, Ohio, Texas and West Virginia. Some school administrators, coaches and teachers said drug testing deters young students from substances of all kinds, including alcohol, marijuana and steroids.

There are no known cases of middle school students testing positive for performance-enhancing drugs, and only a few positive results have been found for marijuana, the article notes.

“Drug testing is a multibillion-dollar industry,” Dr. Linn Goldberg, head of the Division of Health Promotion and Sports Medicine at the Oregon Health and Science University, told the newspaper. “They go to these schools and say it’s great. But do the schools actually look at the data? Schools don’t know what to do.” He added, “There’s little evidence these programs work. Drug testing has never been shown to have a deterrent effect.”

A 1995 United States Supreme Court ruling states that drug testing for high school athletes is constitutional.

In most cases, outside drug testing companies conduct the tests. Students are given little or no notice about them. Specimens are sent to a lab, and families are notified if the result is positive. In some cases, schools require a second test to confirm the finding. Law enforcement generally is not notified if a test is positive.

School punishments can range from a warning, to removal from a team or activity.