N.C. Gen. Stat. § 115C-344

An exchange teacher is a nonimmigrant alien teacher participating in an exchange visitor program designated by the United States Department of State pursuant to 22 C.F.R. Part 62 or by the United States Department of Homeland Security pursuant to 8 C.F.R. Part 214.2(q). For purposes of determining eligibility to receive employment benefits under this Chapter, including personal leave, annual vacation leave, and sick leave, an exchange teacher shall be considered a permanent teacher if employed with the expectation of at least six full consecutive monthly pay periods of employment and if employed at least 20 hours per week. An exchange teacher is not a teacher for purposes of the Teachers' and State Employees' Retirement System of North Carolina as provided in G.S. 135-1(25).