The South Dakota law is found at Section 13-36-9 through 13-36-14 of the South Dakota Code, under the education title. (S.D. Codified Laws §§ 13-36-9 through 13-36-14).
South Dakota law requires that a concussion information sheet be developed by each school district and annually signed and returned by parents/guardians prior to a student participating in an athletic activity. The South Dakota High School Activities Association and the South Dakota Department of Education are required to develop a concussion training program, which every coach participating in athletic activities sanctioned by the South Dakota High School Activities Association shall complete each academic year. The law also provides that any athlete exhibiting signs or symptoms or suspected of sustaining a concussion shall be immediately removed from participation in any athletic activity sanctioned by the South Dakota High School Activities Association and may not return until evaluated by a licensed health care professional, given written clearance to return, and no longer exhibiting symptoms of a concussion.
The official versions of these sections are currently available online at:
http://legis.sd.gov/Statutes/Codified_Laws/DisplayStatute.aspx?Type=Statute&Statute=13-36 (select desired section)
The following websites offer additional information regarding South Dakota concussion law:
http://www.sdhsaa.com/Portals/0/PDFs/Athletics/Health-Safety/SDConcussionLegislation.pdf
http://www.sdhsaa.com/