The purposes of the drug-testing program are to prevent injury, illness, and harm resulting from the use of illegal and performance-enhancing drugs or alcohol; help enforce a drug-free educational environment; deter student use of illegal and performance-enhancing drugs or alcohol; help students avoid peer pressure. 

URINE TESTING - Many illicit substances are detectable for as little as 2-30 days in urine, depending on drug used, dose, and route of administration.  

ORAL FLUID (SALIVA) TESTING-Depending on the drug used, dose, and route of administration, a drug may be detected in oral fluid in less than one hour and remain detectable for five up to 48 hours after last use 

What are the guidelines for mandatory drug testing of students?  What is the TEA  policy on random drug searches?

Section 33.091, Education Code, governs the random testing of student athletes for illegal  steroid use, which the University Interscholastic League is required to conduct.  Otherwise,   there are no state guidelines or policies regarding drug testing or drug searches.  School  districts are authorized to enact policies for safety and security under Chapters 37 and 38 of the Texas Education Code. School district policies and practices in this area need to be designed to be consistent with judicial decisions analyzing issues in this area with regard to the constitutional  limitations on search and seizure.