Final answer:
The U.S. Supreme Court has ruled that it is legal for public high schools to conduct urine tests on students for drug screening, especially for those participating in extracurricular activities or athletics.
Step-by-step explanation:
The question asks whether it is legal to use urine tests to screen students in public high schools for drug use according to the U.S. Supreme Court. The answer is true; according to the Supreme Court rulings in the cases Board of Education v. Earls (2002) and Vernonia School District 47J v. Acton (1995), it is indeed permissible. The prior case confirmed that drug testing for students who participate in extracurricular activities does not violate the Fourth Amendment, and the latter upheld the right of schools to conduct random urine tests on students involved in school-sponsored athletics.