"Recent national estimates indicate that 14 percent of U.S. public school districts conducted random drug testing in at least one of their high schools during the 2004–2005 school year (Ringwalt et al. 2008), and since 2003, the U.S. Department of Education’s Office of Safe and Drug-Free Schools (OSDFS) has operated a grant program to support MRSDT programs in schools."

Source

Burdumy, James; Brian Goesling, Susanne; Deke, John; and Einspruch, Eric (2010). The Effectiveness of Mandatory-Random Student Drug Testing (NCEE 2010-4025). Washington, DC: National Center for Education Evaluation and Regional Assistance, Institute of Education Sciences, U.S. Department of Education, p. 1.
http://ies.ed.gov/ncee/pubs/2…