Grayslake High School District 127 spent $40,000 on random drug tests for students last year.
The testing program, which each year tests about 1,000 students who participate in sports or activities, has been in place for almost 15 years. Some years, no students test positive. Some years as many as seven have produced positive tests.
Officials said the cost has been worth it.
"If this program prevents even one student from engaging in substance abuse, it has been a huge success," Superintendent Catherine Finger said.
But after being the third school in Illinois to start drug testing students in 1999, Grayslake is still an exception among suburban public schools.
St. Viator High School in Arlington Heights made national news last week by announcing a new alcohol testing program to go along with the random drug testing that has been in place since 2007. As a private school, St. Viator is able to test every student as a condition of attendance, something that is not allowed in public schools.
Although public schools can test some students for drugs -- and alcohol, now that the technology is available -- officials said most in Illinois have not adopted testing programs because of expense, privacy concerns, parental outcry and alternative attempts to prevent substance use.
While neither the State Board of Education nor the Illinois Association of School Boards tracks how many schools have testing policies, schools that do test include Zion-Benton, Homewood-Flossmoor, Plano and Sandwich.
"We are all concerned about the welfare of our students and committed to removing any barrier standing between them and their success," Finger said. "The testing program gives students one more reason to say 'no' to peer pressure."
Finger said Grayslake will be switching from urine to hair follicle tests this year, opening the door to explore alcohol testing similar to what St. Viator plans to do.
The U.S. Supreme Court has ruled that schools can randomly test students who participate in sports and extracurricular activities, because those students sign a code agreeing to certain behavior as a condition of participation, said Ed Yohnka, spokesman for the Illinois ACLU.
At Grayslake, students who participate in off-campus senior lunch and those who have parking privileges are added to the pool that's subject to random testing.
The court has not upheld drug testing for all public school students. Plano High School dodges that by asking every parent in the district to sign a consent form. If a student is selected for a random test and there is no consent form, it is considered a positive test.
Schools also have the right to intervene with a mandatory test if a student seems impaired in class or at a school event, Yohnka said.
He questions the cost and effectiveness of testing.
"They don't usually catch many people," he said. "The people who are in an extracurricular activity are also the students who are less likely to be using drugs or alcohol."
Testing may to get another look at some districts as technological advances make it possible to include alcohol.
Naperville Unit District 203, for example, is starting to investigate the cost and legality of testing.
At a June school board meeting, Bob Ross, the district's assistant superintendent for secondary education, said the idea came from students during an annual review of the co-curricular code. Board member Mike Jaensch said testing could be a way to get students who need help into treatment.
The topic of testing hasn't been broached in several suburban school districts.
"We certainly take a number of steps to discourage our students from drinking and drug use, but we have not discussed random testing," said Dave Beery, spokesman for Maine Township District 207.
"If we suspect a student is under the influence, we give them a Breathalyzer test and that system works for us," said Venetia Miles, spokeswoman for Northwest Suburban High School District 214.
All public school districts that participate in Illinois High School Association athletic programs must submit to random tests for performance-enhancing drugs, but that program is run through the state association.
"There has been no discussion about doing anything further," said Palatine-Schaumburg High School District 211 spokesman Tom Peterson.
Although St. Viator said that a majority of its parents support the drug and alcohol program, parental outcry can be a reason public schools choose not to test.
Lake Zurich High School looked into a drug-testing program in 2011, but decided against it after overwhelming parental feedback against the idea. In a parent survey, 76 percent of respondents opposed the drug-testing plan.
"The board's not interested in pushing an issue people aren't interested in," school board President Kathy Brown said at the time.
Steve Pasierb, president and CEO of Partnership at drugfree.org, said the problem isn't that schools aren't discussing drugs and alcohol, but that families aren't.
"Far too frequently, parents lay this issue off on the schools," he said. "It's a family problem, it's a health issue, and it belongs in that context."
Barriers to that conversation include parents who are afraid or don't know how to bring up the topic, those who feel hypocritical because of their own use, or those suffering from what Pasierb calls "not my kid" syndrome -- assuming that their child would not use drugs or alcohol.
Pasierb said he doesn't think drug testing is a magic answer to making teenagers drug-free.
"Our bottom line is that it should be in the parent-child context. It should be the parent's decision if they want their child to be drug tested, not a condition of going to school," he said. "We don't see it as a blanket prevention tool."
According to a study done by the group in 2012, four in 10 teenagers used marijuana in the previous year and 57 percent used alcohol in the previous year -- a 10 percent increase from 2008.
Pasierb said increased use of prescription drugs by teenagers also is a concern.
"Any substance use in your teenage years is a health risk," Pasierb said, citing statistics indicating that 90 percent of adults with an addiction began using as a teen.
But he said drug or alcohol testing is more of a Band-Aid than an actual solution.
"We can't arrest our way out of the problem, and we won't test our way out of the problem," he said. "We have to treat this as a health problem. We need to talk about the health risks of using, not the penalties. There is no silver bullet."